• Korean Journal of Agricultural Science
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• v.6 no.2
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• pp.166-184
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• 1979

In order to prevent the water loss in the irrigation canal constructed on the sandy gravel layer or on the other highly permeable ground layer, lining has been practiced. Many studies have been done so far on the lining method to prevent the water loss in the irrigation canal and recently studies on the lining with plastic film or polyethylene film were also reported. However, the plastic film or polyethylene film has low strength and is liable to break, and water loss from pin hole caused by contacting with sand or gravel is highly predicted. This study was then conducted to find proper lining and buring method in canal construction of polypropylene mat after coated with vinyl, as one way to overcome the shortcoming frequently observed when plastic or usual polyehtylene film were used. Eventhough rather longer periods of experiments are needed to attain reliable and accurate results on the variation of durability, the durability of asphalt coated area, or on the damage due to freeze after burial or exposure of polypropylene mat, the experiemental results obtained during one year of period are summarized as follows: 1. The curvature at the area between canal bottom and side slope had increased stability and saved consruction cost. The relationship among the variation of curvature, the reduction of polypropylene mat and the reduced amount of soil cutting at each side slope was presented in Fig. 7 through 9. 2. The depth of covering material to protect polypropylene mat was desired to be over 30cm, considering the water depth, side slope, canal cleaning practices, traffic, or back pressure of irrigation period. 3. In order to increase the canal stability and to prevent slope erosion, sandy soil was required, to be placed under ground, and coarse gravel should cover the surface area of canal. 4. The studies on the stability of side slope in the canal should consider the passive area on the bottom and the slope should be about 1 to 2, considering the slope stability, allowable velocity and tractive force. 5. When compared with earth lining, the lining with polypropylene mat coated with vinyl was responsible to save 28% and 37% of canal lining cost, when the soil carrying distances were 500 and 700m. respectively. 6. The water interception was almost completely attained when the polypropylene mat coated with vinyl was used for lining. But further studies were assumed to be necessary for the use of asphalt since the strength of polypropylene mat connected with asphalt will vary with duration.

• Korean Journal of Food Science and Technology
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• v.10 no.4
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• pp.387-393
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• 1978

Lipid oxidation is one of the major factors affecting on deterioration of nutritional quality in dried fish products. In this paper, the relationship between oxidized products of lipid and brown pigments, free amino acids and available lysine during the storage of dried sea eel, Muraesox cinereus, was investigated. And the inhibiting effect of antioxidant to lipid oxidation and its role to the protein quality were also discussed. From the results, TBA and carbonyl value rapidly increased while amino-N and available lysine diminished during hot air drying. This suggests that drying conditions greatly affected to the oxidation of lipid and making amino acids 'unavailable'. TBA value increased up to 20 days, and hereafter gradually diminished. Increase in TBA and carbonyl value and formation of fat oxidative brown pigment were closely related to the loss of free amino-N and available lysine. The loss of available lysine seemed to be affected by the formation of unsaturated carbonyl compounds rather than saturated carbonyl compounds. By the treatment of antioxidant, the loss of amino acids and available lysine was somewhat retarded. This may suggests that the oxidation of lipid or oxidative browning reactions are functioning to the loss of available lysine. In antioxidant treated sample, 23% of amino-N to the total amino-N in the fresh sample was lost after 20 days storage at $30^{\circ}C$ while the loss of amino-N to 39% in case of the control, and afterward the value treated to be slightly reduced or remained steady.

• Journal of Nutrition and Health
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• v.6 no.1
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• pp.71-76
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• 1973

1. This survey is somewhat different from that conducted by Yonsei University, although being in many respects, very similar. We found the average per capita caloric intake to be 7 or 8% of what it should be. Of that caloric intake, 84.5% in the model village here and 82.2% in the compared village Bupyong, by and large depends on cereal grains. Since such grains tend to distend the stomach, the farmers, it seems,should substitute fat for a part of their diet so as to dimish digestive pain and still receive the necessary calories. 2. Protein is the most important nutrient for the development of physical strength and improvement of health, but the average daily intake is only 68.3% of the necessary amount. It is desirable that the ratio of vegetable protein to that of animal be one to three for maintaining one's health. Most of the villager's protein, however, comes from plants: the intake of animal protein, at a level of only 13.6 g, is far below such a one to three ratio. 3. In the model village, 497.6 mg, of inorganic calcium is the daily intake level. In the compared village it is 505.5 mg, making a difference of only 8mg. This, however, is 35% less than the recommended intake. More than 50% of this calcium comes from cereals and other plants. Moreover, plant calcium which has much oxakuc acud us not as nutritional as animal calcium, so their calcium diet is less than it would appear. We must, therefore, make efforts to receive as good nutritional calcium as possible. 4. Among the vitamin group, the daily average intake of vitamin A and vitamin $B_{2}$ are respectively 40% and 32% less than the desired intake, while vitamin $B_{1}$ happens to be taken in sufficient quantities and more niacin is taken than which is even necessary. The intake of vitamin C is much more than the necessary quantity. However, this figure was calculated from uncooked food; if the loss from cooking were to be considered, the real intake might well be a little less. Also, as this survey was carried out in May, some of these results were influenced by the fact that lettuce and spinach are seasonally popular. In conclusion, except for a few nutrients which are in abundance, the normal food intake in a day is, on the whole, less than the average recommended. Furthermore despite the fact that both of these places are model villages in the development of nutrition, it seems that they have not gotten out of such conventional eating habiys as the almost dependancy on cereal grains. Cow's milk, sheep's milk, eggs and so on produced by each farmhouse are not used for their own families but are taken to the market for the purpose of making money. Accordingly, I think from now we must seek to improve, guide and enlighten the farmers as to how to correct their eating habits and implement changes in their lives so that our firm purpose may be achieved.

• Journal of Animal Environmental Science
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• v.14 no.3
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• pp.201-210
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• 2008

Farmers directly spread the livestock manure compost on their arable land as an organic fertilizer. However, there are some difficult problems to solve. first, we are unsure of whether the livestock manure compost can meet the nutritional demand of plant. Second, application of the current powered livestock manure compost to crop land is very difficult work due to heavy weight of compost and its powdered shape. For this reason, this study was carried out to develope high quality pelletized livestock manure compost. In pelletizing process with composted manure, the optimal water content for pelletizing was around 30$\sim$40%. When rice bran was mixed with 5% as a bonding agent on volume basis, the pelletizing effect was remarkably improved. On a dry matter basis, the contents of N and P of manure compost were 1.31%, and 0.58%, respectively. After pelletizing, the contents of compost pelleted were 1.37% and 0.54%, respectively. The same parameters of pelletized compost made by screw type Instrument were 1.37% and 0.53%, respectively. The other hand, N and P content of pelletized compost made by pellet mill type instrument were 1.06% and 0.18%, respectively.

• Korean Journal of Agricultural Science
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• v.3 no.1
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• pp.77-84
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• 1976

The preservation efficiency, quality and utilization of silage from 3 species of pumpkins (Mammoth pumpkin, Queensland blue pumpkin, Korean pumpkin) without and with 10, and 20% wheat bran additive were studied in this experiment. Silages were analysised and tested the chemical composition, pH and quality of silages between at 40-60 days and egg performance were carried out with mammoth pumpkin silage without additive. The results were summaried as follows. 1. The losses of all silage ware lower and similar as about 15% at 6 monthes following after silage-making but all raw pumpkins were spoilaged during the winter storaging. 2. The moisture content of silages were higher as about 97% in mammoth pumpkin silage, 94% in Queensland pumpkin silage and 91% in Korean pumpkin silage without additive and all nutrient content of silage without and with additive were depended on its content of raw silage material of pumpkins and wheat bran. The contents of moisture and N-free extract were slightly decrease but not significantly difference during the silaging and other contents were not so much changed. 3. Good quality of silage were made from all pumpkins with and without additive. Organic acid contents were 2.09-2.93% of lactic acid, 0.68-1.71% of acetic acid and 0% of butyric acid and it was pH 3.8-4.0 in silages. 4. Feed intakes, egg production and quality of egg were showed good result in 5.0 and 7.5% silage feeding group as D.M. base for egg performance. (P<0.01) 5. It was concluded that good quality of silage were made from pumpkins with and without wheat bran additive and it was suggested that poor quality feedstuff may be improved it feeding value by extended palatability with pumpkin additive silage.

• Journal of Korean Society of Forest Science
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• v.47 no.1
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• pp.44-51
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• 1980

In order to find out the suitable methods that can omit the earth healing and increase the survival through improving the seedling-healing and transportable methods. Several trials with plastic vinyl have been done and its results are as follows: 1. Though P. rigitaeda seedling have been stored in the black and white vinyl sack for 35 days in the storehouse. This seedling have survived with very high percentage as Table 1. This means that the earth healing work at the nursery or planting area can be omitted if seedling sould be stored in the storehouse by using the vinyl sack. The possibilities of long-period storage in the black and white vinyl sack seem to be come from the reasons that air humidity in the sack is nearly 100% and its air temperature is only around $15^{\circ}C$ with very little difference between day and night time. This sack also can be utilized in place of the planting sack, and though this sack with seedling have been laid under direct sunshine for 1 to 2 days. Any difference between the sack stored in the storehouse has not been observed on the survival specially Table 2. 2. When the bundled seedling have been covered with the black and white vinyl instead of earth healing, even if these seedling have been laid for 18 days under the vinyl. This seedling show us high survival as Table 3. High humidity with nearly 95%, very little difference of air temperature between day and night time under the vinyl and not so big difference between out-and inside temperature could be reasons of high survival to be considered. So through covering by the black and white vinyl. The labour power for earth healing works can be saved also. 3. In order to protect the healed seedling from the direct sunshine and the eva-transpiration. Black vinyl net and reed mat could be effective for this purpose. Because vinyl net could intercept around one to third, reed mat two to third of total solar energy and also suppress more than 50% of total water loss by the transpiration.

• Korean journal of food and cookery science
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• v.12 no.4
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• pp.547-556
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• 1996

The purpose of this study was to invesitage the optimum cooking method, which ingridients mixing ratio and decortication of white and black sesame gruels, were examined by sensory and mechanical tests. As the results of sensory evaluation for the decortication white and black sesame gruels with the levels of 50, 100, 150, and 200％ sesame per rice l00ｇ, the flavor, nutty taste, and the overall preference were increased with the increase of sesame add. The gruel which made with decorticated sesame roafting for 7 minutes was proferable. The gruels 150% decorticated white and black sesame roasted 7 min had better overall preference. In the mechanical measurement for the white sesame gruels, L value tended to be decreased, while ‘a' and ‘b' values as well as viscosity tented to be increased as the sesame ratio and roasting time increased. In black sesame gruels, L value tended to be decreased, while ‘a' and ‘b' values as well as viscosity tended to be increased when sesame ratio was increased. In correlation between sensory evaluation and mechanical measurement of the white and black sesame gruels, color, flavor, nutty taste of sensory evaluation were correlated with the mechanical measurement. The optimal material mixing ratio for gruels was rice 100 g, white and black sesame 150 g, and water 1075 g.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.9
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• pp.279-287
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• 2018

Sealants are an important element of modern architecture and serve as a building protection against weathering by providing barriers against ingress of moisture, air, and other materials. Exposure to a variety of environments often reduces lifespan due to changes in physical, chemical and mechanical characteristics, and UV, humidity, and temperature expansion are important issues that are directly related to durability. In this study, a combined deterioration test chamber was developed to simulate the environment of the open air as an instrument for verifying the durability of structural sealing materials indoors. In order to replicate special weather conditions, such as yellow dust, acid rain, and contamination by microorganisms, it was deemed impossible to replicate the outdoor environment by 100 %, and the results of the results of the results of the external exposure test of the structural sealant and the combined deterioration testing device. As a result of the displacement test of the outdoor exposure test, it was determined that the sealant was breaking apart and that it would be smooth, and the displacement would be up to three times greater than the initial material value of 1 year. The displacement test results of the combined deterioration test device show the tendency to deteriorate, decreasing the elasticity and tensile characteristics. In the case of denatured silicon, the current 400 cycles have been completed to confirm 12 months of degradation of the external exposure. The deformation of the test specimen cannot be verified with the naked eye, so it is considered that the conditions of the specimen are more stable than the silicon sealant. As a result of the outdoor exposure test, if the combined deterioration test device is structured and proposed in the relevant guidance or specification, the anticipated lifespan of 12 months in the actual use environment can be verified indoors and below 3 months later, economically.

• The Korean Journal of Mycology
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• v.7 no.1
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• pp.13-73
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• 1979

These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.