• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.483-491
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• 2014

Double cropping system including paddy field soybean is widely adopted nationwide, due to rise in market price and its higher income than paddy field rice. Sowing date of soybean as a second crop is being delayed depending on first crop's growth period and harvesting time. Due to the increased temperature in October and delayed first frost date, soybean could be harvested without frost damage even in late-plating. Therefore, selection of soybean cultivar which is appropriate for this environment is very important. The effect of sowing date and genotype of soybean on growth and yield was investigated for three planting dates (June 20, July 5, and July 20) with ten cultivars developed for soy-pate production, to figure out plant development and yield pattern in delayed planting. As planting date is delayed, plant height and pod number was decreased and this pattern was more clearly detected in mid-late maturity cultivars. Hundred-seed weight did not show significant changes even in late planting, due to compensations between yield components. Yield reduction of July 20 in contrast to that of June 20 showed that Nampung (9.6%) showed the least yield decline. Maximum yield was achieved from Daepung, Taekwang, and Uram among other soybean cultivars in late planting. Shortening of growth period was strongly detected in reproductive stage while length of vegetative stage was regularly maintained in both early and mid-late maturity cultivars.

• KDI Journal of Economic Policy
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• v.13 no.1
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• pp.65-113
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• 1991

Korea's rapid economic growth of the past thirty years was led by extremely fast export growth under extensive government intervention. Until very recently, the political regimes were authoritarian and oppressed human rights and labor movements. Because of these characteristics, many inside and outside Korea are under the impression that the rapid economic growth was made possible by the government's relentless push for export growth through industrial targetjng. Whether or not the government intervention was pivotal in Korean economic growth is an important issue because of its normative implications on the role of government and the degree of economic policy intervention in a market economy. A good example of industrial targeting policy in Korea is the "Heavy and Chemical Industry (HCI)" policy, which began in the early 1970s and lasted for one decade. Under the HCI policy the government intervened in resource allocation through preferential tax, trade, and credit and interest rate policies for "key industries" which included iron and steel, non-ferrous metals, shipbuilding, general machinery, chemicals, and electronics. This paper investigates the effects of. the HCI policy on the efficiency of capital and the export competitiveness of manufacturing industries. For individual three-digit KSIC (Korea Standard Industrial Classification) industries and for two industry groups, one favored by HCI Policy and the other not, this paper: (1) computes capital intensities and discusses the impact of the HCI policy on the changes in the intensities over time, (2) estimates the capital efficiencies and examines them on the basis of optimal condition of resource allocation, and (3) compares the Korean and Taiwanese shares of total imports by the OECD countries as a way of weighing the effects of the policy on the industries' export competitiveness. Taiwan is a good reference, as it did not adopt the kind of industrial targeting policy that Korea did, while the Taiwanese and Korean economies share similar characteristics. In the 1973-78 period, the capital intensity rose rapidly for the "HC Group" the group of industries favored by the policy, while it first declined and later showed an anemic rise for the "Light Group," the remaining manufacturing industries. Capital efficiency was much lower in the HC Group than in the Light Group, at least until the late 1970s. This paper acribes these results to excess investments in the favored industries and concludes that growth could have been faster in the absence of the HCI policy. The Korean Light Group's share in total imports by the OECD was larger than that of its Taiwanese counterpart but has become much smaller since 1978. For the HC Group Korea's market share was smaller than Taiwan's and has declined even more since the mid-1970s. This weakening in the export competitiveness of Korea's industries relative to Taiwan's lasted until the mid-1980s. This paper concludes that the HCI policy had either no positive effect on the competitiveness of the Korean manufacturing industries or negative effects.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.38 no.2
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• pp.60-76
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• 2020

The purpose of this study was to examine the spatial and visual arrangement characteristics of Imsil Yi Ung-jae's old house's spatial and visual aspects in order to discover the value of landscape and traditional house garden. The results of this study are as follows. Dongchon-village in Dundeok-ri, where old house is located, is a typical form of with "Back to the mountain and facing the water(背山臨水)", and is located in the north of the three streams of water, forming a Jeonchaghugwan(前窄後寬). Dongchon Village, which has a traditional scenic spot between Danguidae(丹丘臺) and Samgyeseokmun(三溪石門), is understood to be the main street of Nojeokbong Peak and Gyegwanbong Peak, which is Ansan(案山), where the "A centipede flying in the sky(飛天蜈蚣形)". Yi Ung-jae's old house is the oldest existing high-priced house in the North Jeolla region and the closing price of a royal family of the Joseon Dynasty, which was arranged by Chunseongjeong(春城正), Yi Dam-son(李聃孫) in the mid-16C. The Japanese Invasion of Korea in 1592 and Japanese colonial era, the loyalty of the gate quarters, the filial piety of the gate quarters, and the faithfulness of the tablet(扁額) and Juryeons(柱聯) are enough to contribute to the rise of the value of a physical house. The men's quarters(Sarangchae), which are placed on a high-pocket or a layout without going against the sloping terrain, have the effect of making the distance as far as possible, enhancing its dignity and hierarchy as a royal building. In addition, the entrance to the main quarters(Anchae) through the four pillar gates(四柱門), the extensive support and the appropriation of the Chaewon(vegetable garden), and the official base for the Anchae are very unique compared to the general nobility. However, in the context of the postwar relationship, the shrine seeks to realize Confucian ideals while harmonizing with nature by arranging wide sponsorships around it. On the other hand, it is confirmed that there was a pond in the form of a circle in a square(方池圓島型) with a relatively large area, which is now disturbed and damaged. Written by the high priced planting species are sponsored pine trees, hackberry, persimmon trees, Japanese apricot flower, Ohmomiji, and plum tree in the side garden, as well as cotyledon trees in the outside garden. However, although flower bed(花階), which is built on the stone axis, is a place that clearly shows the expensive garden, it seems to have lost the texture of the plant due to the extremely high variety of species and the splendor that does not match the plant landscape of the flower world. Yi Ung-jae's old house is highly valuable as it is a portrait house of a prince of the blood in the mid-Joseon Dynasty. Based on these findings, this study proposed a plan to improve the management of high prices that could be met.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.4
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• pp.386-408
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• 1988

A study was conducted to develop a model for estimating evapotranspiration and yield of Chinese cabbages from meteorological factors from 1981 to 1986 in Suweon, Korea. Lysimeters with water table maintained at 50cm depth were used to measure the potential evapotranspiration and the maximum evapotranspiration in situ. The actual evapotranspiration and the yield were measured in the field plots irrigated with different soil moisture regimes of -0.2, -0.5, and -1.0 bars, respectively. The soil water content throughout the profile was monitored by a neutron moisture depth gauge and the soil water potentials were measured using gypsum block and tensiometer. The fresh weight of Chinese cabbages at harvest was measured as yield. The data collected in situ were analyzed to obtain parameters related to modeling. The results were summarized as followings: 1. The 5-year mean of potential evapotranspiration (PET) gradually increased from 2.38 mm/day in early April to 3.98 mm/day in mid-June, and thereafter, decreased to 1.06 mm/day in mid-November. The estimated PET by Penman, Radiation or Blanney-Criddle methods were overestimated in comparison with the measured PET, while those by Pan-evaporation method were underestimated. The correlation between the estimated and the measured PET, however, showed high significance except for July and August by Blanney-Criddle method, which implied that the coefficients should be adjusted to the Korean conditions. 2. The meteorological factors which showed hgih correlation with the measured PET were temperature, vapour pressure deficit, sunshine hours, solar radiation and pan-evaporation. Several multiple regression equations using meteorological factors were formulated to estimate PET. The equation with pan-evaporation (Eo) was the simplest but highly accurate. PET = 0.712 + 0.705Eo 3. The crop coefficient of Chinese cabbages (Kc), the ratio of the maximum evapotranspiration (ETm) to PET, ranged from 0.5 to 0.7 at early growth stage and from 0.9 to 1.2 at mid and late growth stages. The regression equation with respect to the growth progress degree (G), ranging from 0.0 at transplanting day to 1.0 at the harvesting day, were: $$Kc=0.598+0.959G-0.501G^2$$ for spring cabbages $$Kc=0.402+1.887G-1.432G^2$$ for autumn cabbages 4. The soil factor (Kf), the ratio of the actual evapotranspiration to the maximum evapotranspiration, showed 1.0 when the available soil water fraction (f) was higher than a threshold value (fp) and decreased linearly with decreasing f below fp. The relationships were: Kf=1.0 for $$f{\geq}fp$$ Kf=a+bf for f$$I{\leq}Esm$$ Es = Esm for I > Esm 6. The model for estimating actual evapotranspiration (ETa) was based on the water balance neglecting capillary rise as: ETa=PET. Kc. Kf+Es 7. The model for estimating relative yield (Y/Ym) was selected among the regression equations with the measured ETa as: Y/Ym=a+bln(ETa) The coefficients and b were 0.07 and 0.73 for spring Chinese cabbages and 0.37 and 0.66 for autumn Chinese cabbages, respectively. 8. The estimated ETa and Y/Ym were compared with the measured values to verify the model established above. The estimated ETa showed disparities within 0.29mm/day for spring Chinese cabbages and 0.19mm/day for autumn Chinese cabbages. The average deviation of the estimated relative yield were 0.14 and 0.09, respectively. 9. The deviations between the estimated values by the model and the actual values obtained from three cropping field experiments after the completion of the model calibration were within reasonable confidence range. Therefore, this model was validated to be used in practical purpose.

• Journal of Gastric Cancer
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• v.5 no.1
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• pp.10-15
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• 2005

Purpose: Recently the role of vitamins, folate in particular, has been emphasized in the maintenance of health. Folate deficiency is known to give rise to developmental delay, immature vascular disease, neural tube defect, acute leukemia, atherosclerotic vascular disease, delivery defects, breast cancer, and particularly gastrointestinal neoplasia. Methylenetetrahydrofolate reductase (MTHFR) is an essential enzyme in folate metaboism, and influences DNA synthesis and DNA methylation. Generally, folate deficiency is associated with gastrointestinal neoplasms. The amino-acid- changing and enzyme-activity-reducing nucleotide polymorphism (766C$\rightarrow$T/ Ala222Val) has been described in the MTHFR polymorphism and leads to low enzyme activity that may reduce the capacity of DNA methylation and possibly uracil mis-incorporation into DNA. These processes may be critical in the oncogenic transformation of human cells, especially in colorectal carcinomas. We investigated the relationship between the MTHFR polymorphism in gastric cancer and the tumor site, the smoking history, and the alcoholic history. Materials and Methods: Ninety-six (96) individuals with gastric cancer and 287 healthy persons were analyzed. Blood sampling was performed, PCR-RFLP was analyzed, and MTHFR polymorphism genotypes of C/C, C/T, and T/T were obtained and analyzed statistically for their correlation. Results: In the gastric cancer group there were 69 ($72\%$) males and 27 ($28\%$) females. There were also 58 cases ($60\%$) involving the gastric lower body, 20 cases ($21\%$) the gastric mid-body, and 18 cases ($19\%$) the gastric upper body. In the control group there were 169 ($59\%$) males and 118 ($41\%$) females. Among the gastric cancer, 56 ($61\%$) smoking patients, 40 ($39\%$) non-smoking patients, 45($47\%$) alcoholic patients, 51 ($53\%$) non-alcoholic patients. In the gastric cancer group, MTHER polymorphisms were C/C in 18 ($19\%$) cases, C/T in 59 ($61\%$) cases, T/T in 19 ($20\%$) cases. In the control group polymorphisms were C/C 116 ($40\%$) cases, C/T 103 ($36\%$) cases, and T/T 68 ($24\%$) cases (P=0.045). In cases of lower gastric body cancer, polymorphisms were C/C in 16 ($24\%$) C/C in 16 ($24\%$) cases and C/T or T/T in 42 ($72\%$) cases. In cases of upper and mid-body cancer, polymorphisms were C/C in 2 ($5\%$) cases and C/T or T/T 36 ($95\%$) cases (P=0.006). In the non-smoking patient group, polymorphisms were C/C in 5 (12%) cases and C/T or T/T in 35 ($88\%$) cases. In the smoking patient group, C/C in 13 ($23\%$) cases and C/T or T/T in 43 ($77\%$) cases (P=0.189). In the non-alcoholic patient group, polymorphisms were C/C in 6 ($12\%$) cases and C/T or T/T in 45 ($88\%$) cases. In the alcoholic patient group, polymorphisms were C/C in 12 ($26\%$) cases and C/T or T/T in 33 ($74\%$) cases (P=0.063) Conclusion: MTHFR polymorphisms are associated with gastric cancer and tumor site, but not with smoking and alcohol drinking.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.327-338
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• 2020

In recent years, the temperature of Korea has been rapidly increasing due to global warming. Over the past 40 years, the temperature of Korea has risen by about 1.26℃ compared to that in the early 1980s. By region, the west region of the Gangwon Province was the highest at 1.76℃ and the Jeonnam Province was the lowest at 0.96℃. As the temperature continues to rise, it is expected that the rice yield will decrease in the future using the current standard cultivation method. As a result of global warming, the periods in which rice cultivation could be possible in regions each year has increased compared those to the past, showing a wide variety from 110 days in Taebaek to 180 days in Busan and Gwangyang. In addition, the transplanting time was delayed by 3-5 days in all regions. The average annual yield of rice showed an increasing trend when we analyzed the average productivities of developed varieties for cooked rice since the 1980s, especially in the early 1990s, which showed a rapid increase in productivity. The relationship between the average temperature at the time of development and the rice yield was divided into the periods before and after 1996. The higher the average temperature, the lower the yield of the developed varieties until 1996. However, since 1996, the increase in the average temperature did not show a trend in the productivity of the developed varieties. The climate change adaptability of developed rice varieties was investigated by analyzing the results of growing crops nationwide from 1999 to 2016 and the change in the annual yields of developed varieties and recently developed varieties as basic data to investigate the growth status of the crops in the country. As a result of annual comparisons of the yields of Taebongbyeo (2000) and Ungwangbyeo (2004) developed in the early 2000s for Odaebyeo, which was developed in the 1980s, the annual yields were relatively higher in varieties in the 2000s despite the increase in temperature. The annual yields of Samgwangbyeo (2003) and Saenuribyeo (2007), which were recently developed as mid-late-type varieties, were higher than those of an earlier developed variety called Chucheongbyeo, which was developed in the 1970s. Despite the rapid increase in temperature, rice cultivation technology and variety development are well adapted to climate change. However, since the biological potential of rice could reach its limit, it is necessary to develop continuous response technology.

• Journal of Environmental Policy
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• v.9 no.2
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• pp.185-205
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• 2010

Climate change vulnerability assessment based on local conditions is a prerequisite for establishment of climate change adaptation policies. While some studies have developed a methodology for vulnerability assessment at the national level using statistical data, few attempts, whether domestic or overseas, have been made to develop methods for local vulnerability assessments that are easily applicable to a single city. Accordingly, the objective of this study was to develop a conceptual framework for climate change vulnerability, and then develop a general methodology for assessment at the regional level applied to a single coastal city, Mokpo, in Jeolla province, Korea. We followed the conceptual framework of climate change vulnerability proposed by the IPCC (1996) which consists of "climate exposure," "systemic sensitivity," and "systemic adaptive capacity." "Climate exposure" was designated as sea level rises of 1, 2, 3, 4, and 5 meter(s), allowing for a simple scenario for sea level rises. Should more complex forecasts of sea level rises be required later, the methodology developed herein can be easily scaled and transferred to other projects. Mokpo was chosen as a seaside city on the southwest coast of Korea, where all cities have experienced rising sea levels. Mokpo has experienced the largest sea level increases of all, and is a region where abnormal high tide events have become a significant threat; especially subsequent to the construction of an estuary dam and breakwaters. Sensitivity to sea level rises was measured by the percentage of flooded area for each administrative region within Mokpo evaluated via simulations using GIS techniques. Population density, particularly that of senior citizens, was also factored in. Adaptive capacity was considered from both the "hardware" and "software" aspects. "Hardware" adaptive capacity was incorporated by considering the presence (or lack thereof) of breakwaters and seawalls, as well as their height. "Software" adaptive capacity was measured using a survey method. The survey questionnaire included economic status, awareness of climate change impact and adaptation, governance, and policy, and was distributed to 75 governmental officials working for Mokpo. Vulnerability to sea level rises was assessed by subtracting adaptive capacity from the sensitivity index. Application of the methodology to Mokpo indicated vulnerability was high for seven out of 20 administrative districts. The results of our methodology provides significant policy implications for the development of climate change adaptation policy as follows: 1) regions with high priority for climate change adaptation measures can be selected through a correlation diagram between vulnerabilities and records of previous flood damage, and 2) after review of existing short, mid, and long-term plans or projects in high priority areas, appropriate adaptation measures can be taken as per this study. Future studies should focus on expanding analysis of climate change exposure from sea level rises to other adverse climate related events, including heat waves, torrential rain, and drought etc.

• Journal of Environmental Policy
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• v.7 no.3
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• pp.89-120
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• 2008

With petroleum being a major source of energy in Korea, the quantity of petroleum transported via ocean routes is on its way up due to increased consumption. Due to the increase, more than 300 cases of pollution caused by petroleum occur annually. Moreover, the number of oil-spill accidents is also on the rise. Causes of such accidents, not including the disposal of waste oil on purpose, turn out to be human error during navigation or defects in the vessels, showing that most accidents are caused by humans. Therefore, to prevent future oil spills, it is imperative that navigation efficiency be enhanced by improving the quality of navigators and replacing old vessels with newer ones. Nevertheless, such improvements cannot occur overnight, so long- and mid-term efforts should be made to achieve it institutionally. As large-scale oil-spill accidents can happen at anytime along the coastal waters of Korea, it is necessary to set-up institutional devices which go beyond the compensation limit of 92FC. The current special law regarding this issue has its limits in that it prescribes compensation be supplemented solely by national taxes. Therefore, the setting-up of a new 'national fund' is recommended for consideration rather than to subscribe to the '2003 Convention for the Supplementary Fund'. It is strongly suggested that a National fund be created from fees collected from oil companies based on the risks involved in oil transportation and according to the profiteers pay principle. In addition, a public fund should be created to handle general environmental damage, such as the large-scale destruction of the ecosystem, which is distinct from the economic damage that harms the local people. The posterior responses to the large-scale oil spill have always been unsatisfactory because of the symbolic nature of the disasters included in such accidents. Oil-spills can be prevented in advance, because they are caused by human beings. But once they occur, they inflict long-term damage to both human life and the natural ecosystem. Therefore, the best response to future oil-spills is to work to prevent them.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.2
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• pp.59-70
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• 1998

Two-dimensional trend-vector model of sediment transport is first tested in the tidal flat of Garolim Bay, mid-western coast of the Korean Peninsula. Three major parameters of surface sediment, i.e., mean grain size, sorting and skewness, are used for defining the best-fitting transport trend-vector on the sand ridge and muddy sand flat. These trend vectors are compared with the real transport directions determined from morphology, field observation and bedforms. The 15 possible cases of trend vectors are calculated from total sediments. In order to find the role of coarse sediments, trend vectors from sediments coarser than < 4.5 ${\phi}$, (sand size) are separately calculated from those of total sediments. As compared with the real directions, the best-fitting transport-vector model is the "case M" of coarse sediments which is the combined trend vectors of two cases: (1) finer, better sorted and more negatively skewed and (2) coarser, better sorted and more positively skewed. This indicates sand-size grains are formed by simpler hydrodynamic processes than total sediments. Transported sediment grains are better sorted than the source sediment grains. This indicates that consistent hydrodynamic energy can make sediment grains better sorted, regardless of complicated mechanisms of sediment transport. Consequently, both transported vector model and real transported direction show that the source of sediments are located outside of bay (offshore Yellow Sea) and in the baymouth. These source sediments are transported through the East Main Tidal Channel adjacent the baymouth. Some are transported from the subtidal zone to the upper tidal flat, but others are transported farther to the south, reaching the south tidal channel in the study area. Also, coarse sediment grains on the sand ridge are originally from the baymouth, and transported through the subtidal zone to the south tidal channel. These coarse sediments are moved to the northeast, but could not pass the small north tidal channel. It is interpreted that the great amount of coarse sediments is returned back to the outside of the bay (Yellow Sea) again through the baymouth during the ebb tide. The distribution of muddy sand in the northeastern part of study area may result from the mixing of two sediment transport mechanisms, i.e., suspension and bedload processes. The landward movement of sand ridge and the formation of the north tidal channel are formed either by the supply of coarse sediments originating from the baymouth and outside of the bay (subaqueous sand ridges including Jang-An-Tae) or by the recent relative sea-level rise.

• Korean Journal of Ecology and Environment
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• v.50 no.4
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• pp.381-402
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• 2017

In order to investigate distribution of vascular plants along elevational gradient in the Nodong valley of Gyebangsan, vascular plants of eight sections with 100-meter-high were surveyed from the Auto-camping site (800 m) to the top of a mountain (1,577 m). There were a total of 382 taxa: 89 families, 234 genera, 339 species, 7 subspecies, 34 varieties, and 2 forms. As a result of analyzing the pattern of species richness, it showed a reversed hump-shaped with minimum richness at mid-high elevation. As a result of analyzing habitat affinity types, the proportion of forest species increased with increasing elevation. But, the ruderal species decreased with increasing elevation, and then increased at the top of a mountain. As for the proportion of life forms, the annual herbs gradually decreased with increasing elevation, but it did not appear between 1,300 m and 1,500 m and then increased at the top of a mountain. The trees gradually increased with elevation and decreased from 1,300~1,400 m. The vascular plants divided into four groups by using DCA. The arrangement of each stands was arranged in order from right to left on the I axis according to the elevation. The distribution of vascular plants is determined by their own optimal ranges of vegetation. Also, rise in temperature due to climate change affects the distribution of vascular plants, composition, and diversity. Therefore, continuous monitoring is necessary to confirm ecological and environmental characteristics of vegetation, distribution ranges, changes of habitat. Furthermore, plans for conservation and management based on these data should be prepared according to climate change.