• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.407-412
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• 2001

This study was conducted to find out the effect of slow-release nitrogen fertilizer, such as latex coated urea(LCU) and Meister10(MS10) on direct seeded rice in dry soil(DS). Junghwabyeo, and early maturity rice cultivar was grown on the plots which were treated with None-nitrogen. urea. LCU and MS10 plot. Growth characteristic, yield and yield components were investigated. Nitrogen uptake-efficiency and physico-chemical properties of soil before-after experiment were analyzed. Plant height and number of tillers $m^{-2}$ in LCU and MS10 plot at early grow stages were higher than those in urea plot. Plant height and number of tillers $m^{-2}$ grown on the plot of Ms10 plot were higher than those of LCU plot. The number of seedling $m^{-2}$ were no significant differences among None-N, urea, and MS10 plot in DS. Heading date and leaf color were higher with Urea than LCU and MS10 plot. Culm length in LCU and MS10 plot were longer compared with urea plot, but panicle length was similar among with Urea, LCU and MS10 plot. Number of panicles $m^{-2}$ was greater in order of MS10 > LCU > Urea plot. Yield were greater in order of MS10 > LCU > Urea plot. Nitrogen uptake and nitrogen efficiency were greater in order of MS10 > LCU > urea plot. After the experiment, total content of nitrogen in soil was not changed at all treatments, but pH, P and Si of soil were lower than those of before experiment at all treatments.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.6
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• pp.401-406
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• 2001

This study was conducted to find out the effect of slow-release nitrogen fertilizer, such as latex coated urea(LCU) and Meister10(MS10) on direct seeded rice in flooded soil(FS). Junghwabyeo, and early maturity rice cultivar grown on the plots which were treated with None-nitrogen, urea, LCU and MS10 plot. Growth characteristic, yield and yield components were investigated. Nitrogen uptake-efficiency and physico-chemical properties of soil before-after experiment were analyzed. Plant height and number of tillers $m^{-2}$ in LCU and MS10 plot at early grow stages were higher than those of Urea plot. MS10 and LCU plot showed similar tendency on the plant height but MS10 plot was higher than LCU plot on the number of tillers $m^{-2}$. The number of seedling $m^{-2}$ were no significant differences among None-N, urea, and MS10 plot. Heading date and leaf color were no significant differences among None-N, urea, and MS10 plot. Culm length in LCU and Ms10 plot were longer compared with urea plot, but panicle length were similar among with Urea, LCU and MS10 plot. Number of panicles $m^{-2}$ was highest in MS10 plot and it was similar between LCU and Urea plot. Yield were greater in order of Ms10 > LCU > Urea plot. Nitrogen uptake and nitrogen efficiency were greater in order of MS10 > LCU > urea plot. After the experiment, total content of nitrogen in soil was not changed at all treatments, but pH, P and K of soil were lower than that of before experiment at all treatments.

• Journal of the Korea Organic Resources Recycling Association
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• v.6 no.2
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• pp.45-57
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• 1998

The object of this experiment was to determine the optimum mixing ratio of paper mill sludge and sewage sludge with woodchips as a bulking agent. The bulking agent was mixed with the mixture of paper mill sludge and sewage sludge(2:1 by dried weight) at the rates of 0(W-0), 20(W-20), 33(W-33), and 50(W-50)% on volume basis, and then the mixtures were composted by forced aerated static pile. The changes of physicochemical properties of the mixtures were measured during the composting in order to evaluate the maturity of composts. The temperatures of W-30 and W-50 treatments increased rapidly as soon as the composting started, and reached $60^{\circ}C$ in the fifth day of composting. Reduction of hot water soluble C/N ratio of W-33 and W-50 treatments showed faster than that of W-0 and W-20 treatments at early stage of the composting. The contents of hot water soluble $NO_3{^-}-N$ showed little change in the early stage of the composting in all treatments, but increased rapidly after 20 days of the composting, and the contents of W-0 among all treatments were lower than the others. The G.I. values of W-50 treatment were over 80 before 20 days after starting the composting, those of W-0 treatment were over 80 after 30 days. As a result of evaluation of compost, W-33 and W-50 treatments were found very reasonable at the mixing ratio of a bulking agent. But it is very difficult to aerate compost pile for W-50 treatment than W-33 treatment due to intensified fluctuation of temperature. Considering cost, availability of a bulking agent, and productivity of compost, W-33 treatments more efficient than W-50 treatment.

• Korean Journal of Agricultural and Forest Meteorology
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• v.15 no.1
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• pp.26-39
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• 2013

Yield reduction in major cereal grains seems unavoidable with the existing cropping systems under the projected climate change in Korea. Crop models were used to predict the effects of planting date shift on grain yields of rice, winter barley and soybeans at 64 agroclimatic zones in Korea. The shift of planting date by 7, 14, and 21 days before and after the recommended planting dates were incorporated in DSSAT experiment files to simulate growth, development and grain yields of major cereal crops. These included 3 rice cultivars representing early-, medium- and late-maturity groups, 1 winter barley and 1 soybean cultivars. Partial mitigation in yield reduction was found with earlier planting in the early maturing rice cultivar and with delayed planting in the late maturing rice cultivar under the RCP8.5 projected climate change in Korea. Additional yield increase in winter barley was expected by earlier planting treatments. Soybean showed a positive effect on grain yield with earlier planting. However, the rate was much lower than the case with winter barley and delayed planting caused yield reduction.

• Current Research on Agriculture and Life Sciences
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• v.15
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• pp.7-16
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• 1997

The effects of liming and inoculation of nodule bacteria on the growth and yield of soybeans in the 1st and 3rd year paddy-upland rotated paddy fields was investigated. Compared with the 1st rotated field, the degree of nodulation was much higher in the 3rd rotated one with greater difference at flowering stage than at the early stage of soybean growth. At the same time, greater difference in the degree of nodulation was also recognized between soybean varieties. In the 3rd year rotated field, a great deal of nodulation effect was recognized in the no-limed field but not in the limed one. The growth of soybean was not much affected by liming and nodulation at early stage but it was much increased by liming at flowering stage, especially in Williams 79, indeterminate type variety. Most of yield components and yield of soybean at maturity was much increased by liming with greater in Williams 79 than in Namhaekong. Nodulation effect on the yield components and yield was great in the no-limed filed but not in the limed one for both varieties. The yield and yield components of soybean, without no relation with liming and nodulation, was much great in the 3rd year rotated paddy fields than in the 1st year one, which was inferred that the more rotated fields the more yield and better growth of soybeans could be possible in the paddy-upland rotatonal soybean croppings.

• Korean Journal of Ichthyology
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• v.13 no.1
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• pp.6-18
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• 2001

Larvae of the gunnel Pholis fangi were collected in coastal waters off Daecheon with a bag net from March to June, 1988, and with a ring larva net in February 1989. Maturity and spawning period were analyzed by examination of the gonads of adult fish collected with a bag net from May 1998 through November 1999. In February, the larvae were widely distributed in the outer and inner Cheonsu Bay. From March to April the larvae were present mainly the inner bay; they were absent there in May and found mainly in the outer bay. After June, few gunnel larvae were collected in the study area. This suggests a seaward movement of gunnel from the nursery grounds of the bay to offshore feeding grounds. The otolith of larvae smaller than 10 mm in total length did not show a distinct growth stop. The growth stop is believed to be formed in the early larval stage when the total length is about 10 mm. This period coincides with the time of shoreward migration, suggesting a metabolic change during this period. At a total length of 30 to 40 mm, the shape of the otolith changes from spherical to elongate. Daily growth rate in length was estimated by the Gompertz equation, which is represented as follows: TL = 6.702exp{2.925"1-exp (-0.008 t)"} ($r^2=0.94$, N = 92) Assuming daily deposition of growth increments in the otolith, the time of first growth increment formation was shown to be from December to January. Gonad observations show that Pholis fangi spawns from November to December. So, the hatching time is thought to be about one month.

• International Commerce and Information Review
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• v.7 no.4
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• pp.387-407
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• 2005

This paper is to study globalization motives and strategies of Japanese and Korean industries by analyzing the causes and patterns of foreign direct investment (FDI) of the firms of the two countries during the 1980s and 1990s. First we develop a FDI function from the profit maximizing model of firms. Then we use regression analysis to determine internally driving-out factors and externally-inducing factors. Japanese FDI strategy has gone through three different stages; from natural resource-seeking investment in the 1950s and 1960s to market-expansion investment in the 1970s and 1980s and to a combination of cost-reducing (low-cost labor-seeking) investment and market-penetrating investment in the 1990s. On the other hand, Korean FDI behavior has gone through four different stages; from the learning stage with small investments in the 1970s, to natural resource-seeking investment in the early and mid 1980s, to the growth stage in the late 1980s and the early 1990s, to the maturity stage of the mid and late 1990s. The last two stages were characterized by a combination of cost-reducing investment and market-seeking investment. As a late comer, Korea began its FDI two decades later than Japan, but caught up the patterns of Japanese FDI by the mid 1990s and is in a competing position with Japan. Our findings show that both Japanese FDI and Korean FDI in Asia and other developing countries tendto be in labor-intensive sectors where their firms are losing their comparative advantages at home. The main motive for FDI into these regions is low-cost resource seeking. On the other hand, both Japanese FDI and Korean FDI in the U.S. and Europe tend to be knowledge-intensive sectors where Japanese and Korean firms attempt to internalize transaction and information costs by globalizing its production. The main motive for FDI into these regions is market-seeking. Firms in both countries have increased their investments in Mexico and Western and Eastern Europe in order to penetrate large economic blocs such as the EU and NAFTA area. Korean firms are more aggressive in expanding into new and untested markets than are their counterpart in Japan. Evidence of this can be seen in the scarcity of Japanese FDI and abundance of Korean FDI in Eastern Europe and China.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.3
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• pp.310-315
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• 2012

The vegetable perilla is proved to be a late-maturing plant that flowers at the early of Oct. regardless of sowing time, so that the sowing time for seed production should be decided under consideration of maturity before beginning of frost. This experiment was carried out to determine the sowing date for seed production at greenhouse on late-maturing perilla cultivar, 'Ipdlkkae 1' in the middle region of Korea. The sowing dates were 8 times from May 6 to July 15 with an intervals of 10 days. As sowing date was delayed, the stem height, no. of nodes, no. of branches, no. of cluster per plant and no. of capsules per cluster were decreased. But as sowing was early, the lodging was occurred because of heavier growing. Days to flowering was linearly decreased about 0.86 day as affected by a day's delayed. But days from flowering to maturing was not significantly affected by sowing date. The grain yield was not significantly different among sowing from May 6 to June 15 and rapidly decreased the sowing after June 25 because of the reductions of no. of cluster and percent of ripened grain. Considering accumulative temperature, lodging, germination rate and grain yield, it is suggested that the sowing for seed production in late-maturing perilla cultivar should be finish before June 15 (transplanted at July 15) at greenhouse in the middle region of Korea.

• Applied Biological Chemistry
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• v.18 no.4
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• pp.219-227
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• 1975

In order to investigate the possibility of wine-making with the grape variety cultivating in Korea, the basic analysises were carried out; analysis of the grape maturity during ripening period, the composition of grape juice, and the chemical components of wine from different varieties. Also the yeasts existing naturally on the grape were isolated and identified. For the selection of strain, the characteristics of 6 strains were studied. The results obtained were summarized as follows. 1. The reducing sugar content increased considerably during two weeks after the ordinary grape-gathering period. 2. The sugar content was highest in Muscat bailey A, which could be fermented naturally. The other varieties, Campbell Early, Steuben, and Alden needed chaptalisation for wine-making. 3. The permanaganate number and the methanol content of wine from all varieties were lower than french wine. 4. The sensory evaluation of wine showed that the pink wine was appreciated better than the red wine of same variety and the foxy taste of wine from hybrid grape influenced little to Korean. 5. The selected 6 strains were identified as Saccharomyces chevaliers, Saccharomyces capensis and Saccharomyces globosus. The strain No. 3 and No. 4 showed the most excellent characters for wine-making.

• Korean Journal of Veterinary Research
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• v.32 no.1
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• pp.143-151
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• 1992

Sixty Four fresh and 142 frozen embryos of dairy cattle were transferred to synchronized dairy, beef or Korean Native Cattle nonsurgically at National Animal Breeding Institute from 1985 to 1990. The results obtained were as follows ; 1. The pregnancy rate of fresh embryos(39.1%) was higher than that of frozen embryos(32.4%) and average pregnancy rate was 34.5%. 2. The pregnancy rate of grade 1 embryos was higher than that of grade 2 embryos for both fresh(41.3% vs 33.3%) and frozen embryos(35.4% vs 25.6%). 3. The pregnancy rate according to development stage of fresh embryos was increased with maturity as 29.2%, 33.3%, 50.0% and 54.5% for morula, early blastocyst, blastocyst and expanded blastocyst, respectively. For frozen embryos, the pregnancy rate of blastocyst(44.4%) was higher than those of morula(31.3%) and early blastocyst(28.0%). 4. The pregnancy rate according go recipient-donor synchrony for fresh embryos was higher when the recipients exhibited estrus 1 day earlier than the donors(43.8%) than when the recipients exhibited estrus 1 day later than the donors(38.1%) or when the recipients and donors exhibited estrus at the same time(37.0%). For forzen embryos, the pregnancy rate was decreased when the recipients and donors exhibited estrus at the same time(37.9%), when the recipients exhibited estrus 1 day later than the donors(32.0%) and when the recipients exhibited estrus 1 day earlier than the donors(23.5%), in sequence. 5. The pregnancy rate of heifers was higher than that of cows for both fresh(50.5% vs 37.9%) and frozen embryos(39.7% vs 25.7%). 6. The pregnancy rate according to recipient breed for fresh embryos was higher in dairy cattle(42.1%) and beef cattle(40.%) than in Korean Native Cattle(33.3%). For frozen embryos, the pregnancy rate was decreased beef cattle(39.1%), dairy cattle(30.3%) and Korean Native Cattle(14.3%), in sequence. 7. The pregnancy rate according to equilibrium steps of glycerol and freezing rate was higher when transferred after 3-steps equilibrium and freezing by the rate of $0.3^{\circ}C$/min from $-6^{\circ}C$ to $-35^{\circ}C$ and $0.1^{\circ}C$/min to $-38^{\circ}C$(39.4%) than when transferred after 6-steps equilibrium and freezing by the rate of $0.5^{\circ}C/min$ from $-6^{\circ}C$ to $-30^{\circ}C$(30.3%).