• KOREAN JOURNAL OF CROP SCIENCE
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• 제42권5호
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• pp.579-596
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• 1997

A simulation study was carried out to delineate potential effects of the lake-induced climate change on crop productivity around Lake Imha which was formed after a multi-purpose dam construction in Andong, Korea. Twenty seven cropping zones were identified within the 30 km by 25 km study area. Five automated weather stations were installed within the study area and operated for five years after the lake formation. A geostatistical method was used to calculate the monthly climatological normals of daily maximum and minimum temperature, solar radiation and precipitation for each cropping zone before and after the dam construction. Daily weather data sets for 30 years were generated for each cropping zone from the monthly normals data representing "No lake" and "After lake" climatic scenarios, respectively. They were fed into crop models (ORYZA1 for rice, SOYGRO for soybean, CERES-maize for corn) to simulate the yield potential of each cropping zone. Calculated daily maximum temperature was higher after the dam construction for the period of October through March and lower for the remaining months except June and July. Decrease in daily minimum temperature was predicted for the period of April through August. Monthly total radiation was predicted to decrease after the lake formation in all the months except February, June, and September and the largest drop was found in winter. But there was no consistent pattern in precipitation change. According to the model calculation, the number of cropping zones which showed a decreased yield potential was 2 for soybean and 6 for corn out of 27 zones with a 10 to 17% yield drop. Little change in yield potential was found at most cropping zones in the case of paddy rice, but interannual variation was predicted to increase after the lake formation. the lake formation.

• Journal of Korean Society of Forest Science
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• 제80권1호
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• pp.32-41
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• 1991

This study is focusted to the national park of Korean typical mountain Chi-ri, its visual resources of forests, and practiced inspectind course by way of hypothesis and tests, to show visual resource management objectively, and that of quantitative basic data. spatial image structure measured by Semantic Differential(S.D.) Scale was shown through factor analysis algorithm for the analyzing psychological amount and examined the flowing out of decisive factor and the objective importance related mutual factors by appling the measurement of visual quality. Also, it has been investigated the differences between the degrees of expectation which is used before and of satisfaction which is used, by appling instrumental expectation theory. And showed patterns of investigation area through factor analyzing algorithm. As a national Park, visual factors that have natural landscape harmonized forest, sky, surface of the water, curious stones and rocks, temples should be escalate their values affirmatively so as to be the scenery of pointed direction and enjoyable, and it is needs the techniques visual resource management and its controlling technique to make artificial structures more intentional planning and systemical setting. Manmade distinctive quality in the spatials that affect complementally or harmonizingly, should be received considering relations between the distifution and joining which in line with various visual presenting massive factors. More than that, it is needed united basic standard to the beauty of arrangements which contain visual continuity considered balance between nature and human work, simplicity of structural types, assimilation, emphasis, unification of different factors and pro rata.

• Journal of Life Science
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• 제22권10호
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• pp.1392-1398
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• 2012

This study investigated the effects of diet of different forages on growth performance and carcass characteristics of Hanwoo steers. Twenty-one Hanwoo steers were randomly allocated to three groups (fed hay, reed, and reed with rice straw) of seven steers each. Initial and final body weights of control, T1, and T2 groups were 125.5, 128.3, 128.3 kg and 697.4, 614.6, 706.7 kg, respectively. Average daily gain tended to increase in controls (0.70 kg/d) and the T2 group (0.71 kg/d) but not as much in the T1 group (0.60 kg/d); however, there was no significant difference. DMI was not significantly different among the treatment groups, but T1 was relatively lower than the other groups. For the yield traits, carcass weight was not significantly different between controls and the T2 group but was greater in the T2 group compared to the T1 group (p<0.05). Back fat thickness and rib eye area were higher in controls and T2 compared to T1; yield grade (A:B:C, %) was greater in T1 (43:57:0) compared to the other groups (control 0:71:29; T2 29:42:29). For the quality traits, fat color and texture were not significantly different among groups. However, meat color and maturity were significantly greater in T1 compared to T2 (p<0.05). Marbling score and appearance rate of over 1st meat quality grade were greater in the control and T2 groups compared to the T1 group. Based on the results, growth performance, feed utilization, and carcass traits appeared to improve when roughage containing rice straw plus reed was offered. Therefore, reed is worth considering as a roughage source for fattening Hanwoo steers.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• 제28권4호
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• pp.120-126
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• 2010

As the importance of an historical area is getting increased in these days, the reconstruction of an bell chamber in Namhansansung has significant historial, educational and cultural meaning. The purpose of this study, as a study on an bell chamber in Namhansansung, is to assume an original location of the bell chamber and identify the size and shape of the original bell chamber through literature study, site inspection, and analysis on old maps. In addition, this study could provide useful information when new bell chamber is constructed. According to the literature study, site inspections(5 times) and analysis on old maps, the original bell chamber is assumed to locate near current Oroji tea house at the rotary, where was in the area of Hanggung. With regard to the traffic system, it is assume that there was an old road along with the current local road No.342 connecting the South Gate with North Gate and a Y or T shape intersection connecting the site of old bell chamber with the north. In addition, there was a government office street from the old bell chamber to Hanggung. The shape of old bell chamber is assumed to have Paljak or Woojingak roof. Samo roof was not found in all the five maps. Regarding the direction of bell chamber, three maps indicate that it faces the East and two maps show that it faces the South. Therefore, it is assumed that the length and width of the roof have similar size. However, a new bell chamber should face the East, which is the same direction with Hanggung. As there is a record which states that a bell in the Cheonheoungsa, Seonggeosan, Cheonan was used as a Namhansansung's bell when the Cheonheoungsa was closed, this study suggests that new Namansansung's bell should be built, considering histroical value and artistry of Cheonheoungsa's bell. This study is a basic research for the reconstruction of Namhansansung in 2009. However, as reconstruction of historical assets should be based on thorough historical evidences. Therefore, more detail researches by a indicator analysis are left for the topic of future studies.

• Korean Journal of Agricultural and Forest Meteorology
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• 제8권2호
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• pp.45-53
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• 2006

The objectives of this study are to determine the primary yield components responsible for yield differences in a subtropical environment of the Hunan province China and in a temperature environment of Honam province Korea. Field experiments were conducted in a subtropical environment in Hunan province China during 2002 and in a temperate environment in Honam province Korea during 2003. Seven rice cultivars were grown under optimum crop management in each experiment field. Yield, yield components and plant dry matter were determined at maturation. The highest yield (567 kg/10a) was produced at Honam province by Jinyou 207, a Chinese cultivar, The maximum yield at Hunan province was 453 kg/10a by Sanyou 63. On the average across cultivars, Honam produced 23% greater yields than Hunan. Sink size (spikelets per $m^2$) was responsible far these yield differences. Panicle number per $m^2$ was much greater at Honam.

• Korean Journal of Soil Science and Fertilizer
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• 제3권1호
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• pp.23-28
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• 1970

The effect of wollastonite and manganese dioxide on the growth of rice on an acid sulfate soil were investigated in pot experiment. 1. Since aluminum content in the leachate of soil was reduced with increasing the pH and these chemical changes in the leachate were more pronounced by applying wollastonite, aluminum toxicity in flooded paddy rice was overcome by applying wollastonite, or flooding. 2. Poor growth of rice with iron toxicity-like symptoms on the untreated acid sulfate soil may be caused by excess iron and sulfur. Plants applied wollastonite, however, grew normally and did not show any symptoms. Iron and sulfur contents in the plant was reduced by applying wollastonite. 3. Because of the iron content in the both leachate and plant can be lowered by applying wollastonite, iron-toxicity was averted by applying the wollastonite. 4. Application of manganese dioxide in combination with wollastonite did not counteracted iron content in the plant as compared with the wollastonite treatment. 5. The application of wollastonite increased the dry weight of straw and grain yield. Manganese dioxide with wollastonite caused the increase of number of spickelets per panicles and ripened grains as compared with wollastonite. 6. From these results it can be concluded that the major cause of the poor growth of rice on acid sulfate soil is iron toxicity and the Fe-toxicity can be reduced by application of wollastonite.

• Journal of The Korean Society of Grassland and Forage Science
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• 제32권1호
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• pp.15-28
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• 2012

This study was carried out to know adaptability and growth characteristics, yield, chemical compositions and nutrition yield of corn hybrids for silage at paddy field. The field experiments were conducted at Sangju province for one year (2009). The experimental design was arranged in a randomized block design with three replication. The treatments consisted of eleven corn hybrids. The planting date was on 1 May and harvested at 24 August. Stem diameter, stem hardness and number of ear were higher in P32P75 than other varieties. Ear height, dead leaf and green degree were highest in $NC^+$7117, but number of root system and Brix ($B^{\circ}$) were higher in P3394 than other varieties. Crude protein and crude fat (EE) were highest in P32K61 and P31P41, respectively (P<0.01). NDF and ADF were highest in KPO and KIO, respectively, but no significant differences were found among the varieties. Total mineral contents were the highest in Kwangpyongok (9,775 mg/kg), and P3394 (6,651 mg/kg) was the lowest as compared to other varieties (P<0.01). Crude protein yield, crude fat yield and mineral yield were highest in P3156, P31P41 and KPO, respectively (P<0.01). Total composition amino acid and total fatty acid were the highest in P32K61 and KIO, respectively (P<0.01). Yields of crude protein, fatty acid, composition amino acid and TDN were the highest in P3156 (P<0.01). But yields of crude protein and mineral were the highest in P31P41 and KPO, respectively (P<0.01). Total digestible nutrient (TDN) was higher in order of P3156 > $NC^+$7117 > P31N27 > KPO > P32K61 > P32T83 > P32P75 > P31P41 > P3394 > P32W86 > KIO. Based on the above results, corn hybrid varieties could be recommended in P3156, NC+7117 and P31N27 for growth characteristics, quantitative production and nutrition yield.

• Journal for History of Mathematics
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• 제22권2호
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• pp.27-52
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• 2009

This article discusses the contributions of the leader Oswald Veblen, who was the president of AMS during 1923-1924. In 2006, Korea ranked 12th in SCIE publications in mathematics, more than doubling its publications in less than 10 years, a successful model for a country with relatively short history of modern mathematical research. Now there are 192 four-year universities in Korea. Some 42 of these universities have Ph.D. granting graduate programs in mathematics and/or mathematical education in Korea. Rapid growth is observed over a broad spectrum including a phenomenal performance surge in International Mathematical Olympiad. Western mathematics was first introduced in Korea in the 17th century, but real significant mathematical contributions by Korean mathematicians in modern mathematics were not much known yet to the world. Surprisingly there is no Korean mathematician who could be found in MaC Tutor History Birthplace Map. We are at the time, to have a clear vision and leadership for the 21st century. Even with the above achievement, Korean mathematical community has had obstacles in funding. Many people thinks that mathematical research can be done without funding rather unlike other science subjects, even though they agree fundamental mathematical research is very important. We found that the experience of early American mathematical community can help us to give a vision and role model for Korean mathematical community. When we read the AMS Notice article 'The Vision, Insight, and Influence of Oswald Veblen' by Steve Batterson, it answers many of our questions on the development of American mathematics in early 20th century. We would like to share the story and analyze its meaning for the development of Korean Mathematics of 21st century.

• Journal of Bio-Environment Control
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• 제10권1호
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• pp.15-22
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• 2001

A soil temperature was known as extremely important factor in terms of measuring the values of the growth and yield of vegetable in the greenhouse. A low temperature water irrigation was had much trouble in its growth. This study was performed to analyze the effect of the heating water irrigation on the soil temperature and the growth of a cucumber within a greenhouse environment. Soil temperature was 5-7$^{\circ}C$ below to 10cm in depth and 2-3$^{\circ}C$ to 20cm when the irrigation water temperature was 13$^{\circ}C$ (non-warme water irrigation). Soil temperature was similar to irrigation water temperature at 5cm in depth and was 1.5-2$^{\circ}C$ below at 10cm when the irrigation water temperatures were 2$0^{\circ}C$, $25^{\circ}C$. The early growth rates of heating water irrigation were 109-110% in plant height, 107-108% in leaf number, 103% in node number compared with those of unheated water irrigation for 30 days after planting it. The rates of total yield were 115% in 2$0^{\circ}C$ water irrigation plots and 121% in $25^{\circ}C$ water irrigation plots while those of unheated water irrigation plots were.

• Korean Journal of Soil Science and Fertilizer
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• 제4권1호
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• pp.79-85
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• 1971

The rice variety, Kwanok, was reared in the water, land and salty beds and transplanted to the reclaimed soil area having an average of 0.48% salt concentration 0.67% at the end of April Two levels of $NH_3$-N and urea-N with 6 treatments were used. The effect of each treatment was observed. The plant height of the land bed seedlings at transplanting stage was short but the dry-weight/plant-height ratio was large, and the rooting ability vigorous remarkably after transplantation in the salty area. The total carbohydrate content of the stem part was markedly larger in the land bed seedlings than the others and the C/N ratio was accordingly greater. This tendency was observed through the last rooting stage. In the salty nutrient solution, the roots of salty bed seedlings showed high respiratory activity. The activity of the land bed seedlings did not decreased in the hypertonic solution as much as the water bed seedlings. There was no difference in the effect of fertilization on the rough rice yield between ammonium sulphate and urea. The cultural practices with the land and salty bed seedlings increased the rough rice yields by 33% and 22% respectively, compared with the yields of the water bed Seedlings. The number of panicles, panicle weight and the number of grains per panicle were much greater from the rice plant grown by the land bed seedlings than from the other bed seedlings.