• Korean Journal of Soil Science and Fertilizer
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• v.42 no.6
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• pp.478-485
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• 2009

This study was conducted to reclassify Yongheung series based on the second edition of Soil Taxonomy and to discuss the formation of Yongheung series in Jeju Island. Morphological properties of typifying pedon of Yongheung series were investigated and physico-chemical properties were analyzed according to Soil Survey Laboratory Methods Manual. The typifying pedon contains 3.2~3.4% oxalate extractable (Al + 1/2 Fe), less than 85% phosphate retention, and higher bulk density than $0.90Mg\;m^{-3}$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 15 to 150 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol or Alfisol. The typifying pedon has 0.9 % or more organic carbon in the upper 15 cm of the argillic horizon and accordingly, can be classified as Humult. It has a clay distribution in which the percentage of clay does not decrese from its maximum amount by 20% or more within a depth of 150 cm from the mineral soil surface, and keys out as Palehumult. Also that meets the requirements of Typic Palehumult. That has 35 % or more clay at the particle-size control section and has mesic soil temperature regime. Yongheung series can be classified as fine, mixed, thermic family of Typic Palehumults, not as fine, mixed, thermic family of Typic Hapludalfs. Most soils distributed in the southern coastal areas in Jeju island which have a humid climate are developed as Andisols. But Yongheung series distributed in this areas and derived from mainly trachyte, trachytic andesite, and volcanic ash are developed as Ultisols.

• The Journal of Korean Academy of Prosthodontics
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• v.46 no.4
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• pp.351-358
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• 2008

Purpose: This study examined the recovery of the dentin-resin bonding strength, and the difference in the bonding strength after applying pH hemostatic agents at various pH. Materials and methods: Bosmin, Hemodent, Astregedent, and Visine were used as the hemostatic agents in this study. The Bosmin, Hemodent, and Astrigedent hemostatic agents are acidic, and the Visine hemostatic agent is neutral and is used as a decongestant. Ninety human molar teeth were used as the specimen. The teeth were sectioned using a diamond wheel until the dentin was exposed and wet ground by silica paper. The specimens were divided into two groups according to the hemostatic agent used. The specimens were then subdivided into 9 groups according to the application of re etching (R group) or rinsing only (N group). A commonly used resin bonding procedure was used in the control group. The resin bonding procedure was managed dentin using celluloid capsule. In addition, the shear bond strength was measured using an Instron. Results: In general, samples with the applied hemostatic agent, with the exception of Visine, had a slightly weak bond that was similar to the control group. In addition, the rinsing only (N) group had slightly weak bond that was similar to the re etching (R) group. Conclusion: The application of a hemostatic agent on the dentin surface does not affect the shear bond strength after application for a short time. In addition, rinsing only can recover the shear bond strength making other management procedures redundant, particularly re etching.

• Korean Journal of Environmental Agriculture
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• v.23 no.2
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• pp.99-103
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• 2004

This study was carried out to determine impacts of burning of barley straw produced from rice-barley double cropping paddy field on air quality by investigating emissions of greenhouse gases ($CO_2$, $CH_4$ and $N_2O$), air pollution gases (CO, $SO_2$, $H_2S$, $NH_3$ and NO) and particulate matters (PM 10 and PM 2.5). When the barley straw at a rate of 4.5 t/ha was burned at open status, the emitted GHGs amounts were $CO_2$ 376.8 kg/l0a, $CH_4$ 1.56 and $N_2O$ 0.06. The amount of CO emission was the largest among air pollution gases. These results showed that the range of $45{\sim}55%$ of total C in barley straw was emitted as $CO_2-C$, followed by CO-C ($6.4{\sim}5.9%$) and $CH_4-C$ ($0.5{\sim}0.7%$). As far as moisture content in barley straw is concerned, the higher moisture content that the barley straw contains, the larger amount of air pollution gases and the higher portion of PM 2.5 in PM 10 were emitted when it burned. In case of harvesting time of barley straw, emission amounts of greenhouse, air pollution gases and PM 2.5 portion in PM 10 had tendency to increase when earlier harvested barley straw was burned.

• Journal of the Korean Geographical Society
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• v.30 no.1
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• pp.35-56
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• 1995

During the last two decades, Korea has achieved remarkable economic growth. In this process the nation has become urbanized and industrialized. But we have also encountered widening regional disparity, housing shortage of larger cities, transportation congestion, environmental pollution and many other problems. Rapid increasing urbanization and continuous migration toward Seoul since the late 1960s have been one of the major concerns of government. Government has sought ways to moderate the population increase in Seoul. The regulation which include new town development near Seoul and dispersion strategies of higher education and other administration and living facilities outside of Seoul havemade a great expansion of the spatial influence of Seoul city. Seoul metropolitan reaion has evolved as the most powerful center of political and economical spaces. Generally within a metropolitan region, there exists a growing mutual interdependence economically, as well as socially between a central city and its surrounding area. Seoul metropolitan region manifests itself not only as a coherent system of urbanized regions, but also as an integral part of the daily urban system. The surrounding Gyunggi province and Seoul city become closely linked both economically and functionally, constituting true functlonai urban system. This study is primarily undertaken with the purpose of delineation of the sphere of influence of Seoul city in 1990. At the time of 1985, Seoul metropolitan region was delineated according to the result of the study which was performed by Korea Research Institute for Human Settlements. Afterward, the rapid speed of metropolitanization process with dramatic increase in mobility through the provision of wider transportation system across the Capital region have evolved, resulting in the great expansion of the spatial influence of Seoul city. So this study examines the expanded area of Seoul metropolitan regin during the period of 1985-90. In order to delineate Seoul metropolitan region, the indices of urbanization and functional linkage are selected. Variables included in the measurement of the urbanization level are agricultural structure, population characteristics, manufacturing and service industries, and cultural aspects such as newspaper circulation, the ratio of car ownership and piped water supply. Variables included in the measurement of functional linkage are commuting, shopping pattern, centralized service such as medical facilities and trade of agricultural products. The standardization method and factor analysis are employed in making the delineation of Seoul metropolitan region. According to the result of this study, 2 cities, 8 Eups and 46 Myuns are included Seoul metropolitan region in 1990. If we compare this delineated area in 1990 to that of 1985, we can find the distinctive pattern of expanded axes according to the main transportation routes such as Seoul-Suweon, Seoul-Gwangju, Seoul-Incheon. In 199O, all the Gyunggi province, except a few Myuns located at the north and northwest part of Gyunggi province, are included in Seoul metropolitan region. Furthermore, this study attempts to the analysis of regional structure of Seoul metropolitan region according to the functional characteristics of each city and Gun. Variables included in this analysis are the new residential function, manufacturing function, service function, education and infermation function, public facility function and agricultural function. Factor analysis and cluster analysis are employed in making regionalization. Seoul metropolitan reaion is subdivided into four subregions which reflect different functional specialization. The first group is the specialized region of newly formed residential function. The second group is the specialized reaion of manufacturing function. The third group is the specialized region of service function. And the fourth group has little specialized in terms of manufacturing, service, and residential function. But this region has some potentiality of development when Seoul metropolitan region grow continuously. Seoul metropolitan region accounted for 43% of national population, despite 11.8% of national land size in 1990. Although Seoul metropolitan region enjoys important agglomeration economies, it also has huge social cost in the form of transportation congestion, housing shortage, rapid increase of land value, environment pollution, and etc. Efficient metropolitan plan making is a vital element in promoting Seoul's economic development and providing high quality living environment at low cost. In the light of the result of this study, the outer ring of Seoul metropolitan region, especially northeastern part, are underdeveloped compared to overdeveloped southwestern area. It is needed to develop the guidelines for the implement of the growth control and management plan, inducing more balanced development for whole Seoul metropolitan reaion.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.9 no.2
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• pp.218-226
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• 1998

This study aims at investigating the effects of psychostimulant on functional cerebral localization during the attentional tasks in ADHD. Inclusional subjects were 13 boy between 6-12 years old who met the DSM-IV criteria for ADHD. In each patient, there was a drugfree period(without methyphenidate) and a drug-loaded period(with oral methylphenidate administration), and within each period there was a resting state and a stimulated state with TOVA. Comparisons were made by measuring the amplitudes of four bands(${\alpha}$, ${\beta}$, ${\delta}$, ${\theta}$) of quantitative EEG to see if there were any differences between the drug-free period(resting and stimulated) and the drug-loaded period(resting and stimulated). In the resting state, there was no difference between the drug-free and drug-loaded periods. In the stimulated state with TOVA, the presence of methylphenidate induced significant changes in the theta to beta ratio(${\theta}/{\beta}$) in the right frontal, right parieto-occipital, and left temporal-parietal areas in contrast to the drugf-ree period. These data suggest that methylphenidate shows electrophysiological influences on cerebral topographical activities during the attentional tasks in ADHD.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.20-26
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• 2010

This study was conducted to reclassify Donggui series based on the second edition of Soil Taxonomy and to discuss the formation of Donggui series in Jeju Island. Morphological properties of typifying pedon of Donggui series were investigated and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon has very dark grayish brown (10YR 3/2) silt loam A horizon (0~17 cm), gravelly very dark grayish brown (10YR 3/2) silt loam BA horizon (17~42 cm), gravelly very dark grayish brown (10YR 3/2) silty clay loam Bt1 horizon (43~80 cm), brown (7.5YR 4/6) silty clay Bt2 horizon (80~105 cm), and brown (10YR 5/4) silty clay Bt3 horizon (105~150 cm). It is developed in lava plain and are derived from basalt and pyroclastic materials. The typifying pedon contains 1.3~2.1% oxalate extractable (Al + 1/2 Fe), less than 85% phosphate retention, and higher bulk density than 0.90 $Mg/m^3$. That can not be classified as Andisol. But it has an argillic horizon from a depth of 22 to 150 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol, not as Andisol and Inceptisol. It has udic soil moisture regime, and can be classified as Udalf. Also that meets the requirements of Typic Hapludalf. It has 18-35% clay at the particle-size control section, and have thermic soil temperature regime. Therefore Donggui series can be classified as fine loamy, mixed, thermic family of Typic Hapludalfs, not as fine silty, mixed, thermic family of Dystric Eutrudepts.

• Korean Journal of Environmental Agriculture
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• v.29 no.1
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• pp.27-32
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• 2010

This study was conducted to reclassify Anryong series based on the second edition of Soil Taxonomy and to discuss the formation of Anryong series distributed on the mountain foot slope. Morphological properties of typifying pedon of Anryong series were investigated and physico-chemical properties were analyzed according to Soil survey laboratory methods manual. The typifying pedon of Anryong series has brown (7.5YR 4/4) loam Ap horizon (0-22 cm), strong brown (7.5YR 4/6) cobbly clay loam BAt horizon (22-35 cm), strong brown (7.5YR 4/6) cobbly clay loam Bt1 horizon (35-55 cm), reddish brown (5YR 5/4) cobbly clay loam Bt2 horizon (55-82 cm), and brown (7.5YR 5/4) cobbly clay loam Bt3 horizon (82-120 cm). The typifying pedon has an argillic horizon from a depth of 22 to 120 cm and a base saturation (sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. It can be classified as Ultisol, not as Alfisol. It has udic soil moisture regime, and can be classified as Udult. Also that meets the requirements of Typic Hapludults. It has 18-35% clay at the particle-size control section, and have mesic soil temperature regime. Therefore Anryong series can be classified as fine loamy, mesic family of Typic Hapludults, not as fine loamy, mesic family of Ultic Hapludalfs. Anryong series occur on mountain foot slope positions in colluvial materials derived from acid and intermediate crystalline rocks. They are developed as Ultisols with clay mineral weathering, translocation of clays to accumulate in an argillic horizon, and leaching of base-forming cations from the profile for relatively long periods under humid and temperate climates in Korea.

• Journal of the Korean Society of Radiology
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• v.5 no.5
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• pp.303-308
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• 2011

Background/Aims : The increasing use of diagnostic and therapeutic interventional radiology calls for greater consideration of radiation exposure risk to radiologist and radiological technician, and emphasizes the proper system of radiation protection. This study was designed to assess the effect of a protective grass shield. Methods : A protective grass was following data depth, 0.8 cm; width, 100 cm; length, 100 cm, lead equivalent, 1.6 mmPb. The protective shield was located between the patient and the radiologist. Thirty patients (13 male and 17 female) undergoing interventional radiology between September 2010 and December 2010 were selected for this study. The dose of radiation exposure was recorded with or without the protective grass shield at the level of the head, chest, and pelvis. The measurement was made at 50 cm and 150 cm from the radiation source. Results : The mean patient age was 69 years. The mean patient height and weight was $159.7{\pm}6.7$ cm and $60.3{\pm}5.9$ kg, respectively. The mean body mass index (BMI) was $20.5{\pm}3.0$ kg/m2. radiologists received $1530.2{\pm}550.0$ mR/hr without the protective lead shield. At the same distance, radiation exposure was significantly reduced to $50.3{\pm}85.2$ mR/hr with the protective lead shield (p-value<0.0001). The radiation exposure to radiologist and radiological technician was significantly reduced by the use of a protective lead shield (p value <0.0001). The amount of radiation exposure during interventional radiology was related to the patient' BMI (r=0.749, p=0.001). Conclusions : This protective shield grass is effective in protecting radiologist and radiological technician from radiation exposure.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.341-348
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• 2010

To investigate the effect of continual pre-plant application of liquid pig manure (LPM) on malting barley growth, quality and soil environment in double cropping system of rice and malting barley, the liquid pig manure was applied after harvesting rice and malting barley for 3 years. Field experiment was designed with non-fertilizer, chemical fertilizer (CF) recommended by soil testing, rice (LPM 50%+CF 50%)+malting barley (CF 100%), rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%), rice (LPM 100%)+malting barley (CF 100%) and rice (LPM 100%)+malting barley (LPM 100%). By continuous application of LPM 100%, the contents of available $P_2O_5$ and exchangeable K in the soil were increased. The available $P_2O_5$ increased from 243 to 350 mg $kg^{-1}$ and exchangeable K was changed 0.31 to 0.44 $cmol_{c}\;kg^{-1}$. However, the contents of available $P_2O_5$ and exchangeable K were not significant changes in rice (LPM 50%+CF 50%)+malting barley (LPM 50%+CF 50%) plot. Bulk density of soil was not affected by application of LPM. The microbial density was high in order of bacteria > actinomycetes > fungi. The population of aerobic bacteria in rice (LPM 100%)+malting barley (LPM 100%) plot was higher than other plots. The ratio of aerobic bacteria/fungi and biomass C content were the highest in rice (LPM 100%)+malting barley (LPM 100%) plot. The yield of malting barley was increased 22% by increasing culm length, panicle length, No. of panicle and 1,000 grains as 358 kg $10a^{-1}$ in rice (LPM 100%)+malting barley (LPM 100%) plot compared with 294 kg $10a^{-1}$ in rice (CF 100%)+malting barley (CF 100%) plot. The content of ${\beta}$-glucan was low by 4.5 and 4.4% in non-fertilizer and rice (CF 100%)+malting barley (CF 100%) plot, respectively. The content of crude protein was the lowest by 8.2% in non-fertilizer and rice (CF 100%)+malting barley (CF 100%) plot and the quality of malting barley was good as within 11%.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.289-295
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• 2010

Monitoring of the heavy metals at paddy rice agriculture is very important for environmental agriculture. A study was carried out of heavy metal concentrations in 260 paddy soil samples every four years from 1999 to 2007 in Gyeongnam Province. Heavy metals such as Cd, Cr, Cu, Ni, Pb, Zn, and As in paddy soils were analyzed. Average concentrations of heavy metal were Cd 0.426 (ranged 0.003-1.379) mg $kg^{-1}$ for Cd, 1.189 (0.003-3.264) mg $kg^{-1}$, for Cr, 9.68 (0.05-22.38) mg $kg^{-1}$ for Cu, 2.64 (0.01-7.36) mg $kg^{-1}$ for Ni, 23.7 (0.7-54.1) mg $kg^{-1}$ for Pb, 20.8 (0.7-131.2) mg $kg^{-1}$ for Zn, and 1.054 (0.001-2.110) mg $kg^{-1}$ for As, respectively. Long-term changes of heavy metals were showed that Cd, Ni, and Zn were significantly increased whereas Cr, Cu, and As were significantly decreased. Principle component analysis (PCA) of heavy metals in paddy soils was obtained with eigenvalues > 1 summing 34.3% of variance for PC1, 17.5% of variance for PC2, and 51.8% of the total variance in soil heavy metals.