• Economic and Environmental Geology
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• v.38 no.6 s.175
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• pp.607-622
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• 2005

This study was carried out in order to evaluate where the soil loss was mainly occurred, .and to verify how riverbed sediments in the tributaries of the Seomjin River were related to their source rocks distributed in Sunchang area. The study area including the Seomjin River with 4 tributaries of Kyeongcheon, Okgwacheon, Changjeong-cheon and Ipcheon was divided into 10 watershed. The RUSLE (Revised Universal Soil Loss Equation) was estimated for all the grids (10 m cells) in the corresponding watershed. The amount of soil loss per unit area was calculated as follows: dry fold (53,140.94 tons/ha/year), orchard (25,063.38 tons/ha/year), paddy field (6,506.7 tons/ha/year) and Idlest (6,074.36 tons/ha/year). The differences of soil loss per unit area appear to be depends on areas described earlier. Soil erosion hazard zones were generally distributed within dry fields. Several thematic maps such as land use maps, topographical maps and soil maps were used as a data to generate the RUSLE factors. The amount of soil loss, computed by using the RUSLE, showed that soil loss mainly occurred at the regions where possible source rocks were distributed along the stream. Based on the this study on soil loss and soil erosion hazard zone together with chondrite-normalized REE patterns that were previously analyzed in same study area, a closed relationship between riverbed sediments and possible source rocks is formed. Especially in the Okgwacheon that are widely distributed by various rocks, chondrite-normalized REE pattern derived from the riverbed sediments, source rock and soil is expected to have a closed relationship with the distribution of soil loss.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.508-517
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• 2020

This study aimed to determine the minimum period of aeration treatment of co-digestate to develop it as liquid fertilizer and the chemical changes that occur in the aerobic liquefying process. The co-digestates were divided into three types depending on their additives: swine slurry anaerobic digestate (SS AD), swine slurry 70% + cow slurry 30% anaerobic digestate (SS + CS AD), and swine slurry 70% + apple pomace 30% anaerobic digestate (SS + AP AD). The pH of all co-digestates increased rapidly after 3 days of aerobic treatment, but had slightly decreased in SS AD after 9 days and in SS + CS AD and SS + AP AD after 15 days. All co-digestates showed a strongly reduced pH between 27 and 36 days of aeration treatment. SS AD had lower pH value, dissolved oxygen (DO), NH₄-N, and NO₃-N content under aerobic conditions than other co-digestates. To assess the fully decomposed liquid fertilizer, a germination test was performed on the undiluted and diluted co-digestate using the liquid fertilizer germination index (LFGI) method. The relative germination ratio, relative root elongation, and germination index of SS AD were higher than those of the others. When the LFGI method was used for the germination test, all co-digestates showed an appropriate germination index of 70 after 60 days of aeration treatment. Thus, we suggest that the minimum period of aeration treatment for co-digestates might be 60 days to develop the fully decomposed liquid fertilizer.

• Journal of the Korean Society for Marine Environment & Energy
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• v.17 no.4
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• pp.306-317
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• 2014

This study has been executed to understand the additional and removal processes of nutrients in the Saemangeum Salt-water Lake, and discussed with other monthly-collected environmental parameters such as water temperature, salinity, dissolved oxygen, suspended solids, and Chl-a from 2008 to 2010. $NO_3$-N, TP, $PO_4$-P, and DISi showed the removal processes along with the salinity gradients at the surface water of the lake, whereas $NO_2$-N, $NH_4$-N, and Chl-a showed addition trend. In the bottom water all water quality parameters except $NO_3$-N appeared addition processes indicating evidence of continuous nutrients suppliance into the bottom layer. The mixing modelling approach revealed that the biogeochemical processes in the lake consume $NO_3$-N and consequently added $NH_4$-N and $PO_4$-P to the bottom water during the summer seasons. The $NH_4$-N and $PO_4$-P appeared strong increase at the bottom water of the river-side of the lake and strong concentration gradient difference of dissolved oxygen also appeared in the same time. DISi exhibited continuous seasonal supply from spring to summer. Internal addition of $NH_4$-N and $PO_4$-P in the river-side of the lake were much higher than the dike-side, while the increase of DISi showed similar level both the dike and river sides. The temporal distribution of benthic flux for DISi indicates that addition of nutrients in the bottom water was strongly affected by other sources, for example, submarine ground-water discharge (SGD) through bottom sediment.

• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1385-1390
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• 2006

외국에서 ASM 모델의 BNR 적용 연구결과를 국내 하수에 적용하기에는 하수농도, 온도, 슬러지농도 등이 국내와는 달라 적용상 무리가 있다. 본 연구에서 BNR 시뮬레이션을 위한 입력 자료로 활용되는 인자들은 IAWPRC task group에서 제안하는 값들을 사용하되 국내 하수성상에서 필요로 하는 인자들은 직접 실험을 통하여 부분적으로 구해냄으로써 모델 시뮬레이션의 신뢰도를 높이고자 하였다. F/M비의 변화량과 1/SRT과의 관계로부터, 종속영양미생물 생산계수 $Y_H$값을 구한결과, 0.40mg VSS/mg COD였다. 이것을 ASM No.2d에 적용하기 위하여 mg cell COD formed/mg COD oxidized 단위로 환산한 결과 0.58을 나타냈다. H 하수처리장의 1차 침전지 하수를 이용하여 호기성상태에서 OUR Test를 통한 미생물에 의한 유기물 섭취시 산소섭취율 변화를 측정하였다. 호기성상태와 무산소상태에서 구한 쉽게 분해되는 용존성유기물(Ss)값을 비교해보면 각각 35.5mg/L와 39.9mg/L로 약간의 차이는 있으나 유사한 값을 보여주고 있다. 시뮬레이션을 위한 동력학적 계수 중 무산소 상태에서 종속영양미생물의 ${\mu}_{max,H}$는 $3.56d^{-1}$로 나타났고, 호기성상태에서는 구하면 ${\mu}_{max,H}$는 $4.2d^{-1}$로 산출되었다. 종속영양미생물의 사멸계수 $b_H$를 구하기 위한 실험에서 초기 OUR의 10%이내가 될 때까지 걸린 시간은 7일정도가 걸렸으며, 사멸률 $b_H$는 $0.043hr^{-1}$로 나타났다. 독립영양미생물의 최대비성장률 ${\mu}_{max,A}$는 최대암모니아 섭취률을 이용하여 구한 결과 $0.65d^{-1}$로 나타났다.EX>$60%{\sim}87%$가 수심 10m 이내에 분포하였고, 녹조강과 남조강이 우점하는 하절기에는 5m 이내에 주로 분포하였다. 취수탑 지점의 수심이 연중 $25{\sim}35m$를 유지하는 H호의 경우 간헐식 폭기장치를 가동하는 기간은 물론 그 외 기간에도 취수구의 심도를 표층 10m 이하로 유지 할 경우 전체 조류 유입량을 60% 이상 저감할 수 있을 것으로 조사되었다.심볼 및 색채 디자인 등의 작업이 수반되어야 하며, 이들을 고려한 인터넷용 GIS기본도를 신규 제작한다. 상습침수지구와 관련된 각종 GIS데이타와 각 기관이 보유하고 있는 공공정보 가운데 공간정보와 연계되어야 하는 자료를 인터넷 GIS를 이용하여 효율적으로 관리하기 위해서는 단계별 구축전략이 필요하다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 상습침수구역관련 정보를 검색, 처리 및 분석할 수 있는 상습침수 구역 종합정보화 시스템을 구축토록 하였다.N, 항목에서 보 상류가 높게 나타났으나, 철거되지 않은 검전보나 안양대교보에 비해 그 차이가 크지 않은 것으로 나타났다.의 기상변화가 자발성 기흉 발생에 영향을 미친다고 추론할 수 있었다. 향후 본 연구에서 추론된 기상변화와 기흉 발생과의 인과관계를 확인하고 좀 더 구체화하기 위한 연구가 필요할 것이다.게 이루어질 수 있을 것으로 기대된다.는 초과수익률이 상승하지만, 이후로는 감소하므로, 반전거래전략을 활용하는 경우 주식투자기간은 24개월이하의 중단기가 적합함을 발견하였다. 이상의 행태적 측면과 투자성과측면의 실증결과를 통하여 한국주식시장에 있어서 시장수익률을 평균적으로 초과할 수 있는 거래전략은 존재하므로 이러한 전략을 개발 및 활용할 수 있으며, 특히, 한국주식시장에 적합한 거래전략은 반전거래전략이고, 이 전략의 유용성은 투자자가 설정한 투자기간보다 더욱 긴 분석기간의 주식가격정보에 의하여 최대한 발휘될 수 있음을 확인하였다.(M1), 무역적자의 폭, 산업의 생산

• Tuberculosis and Respiratory Diseases
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• v.39 no.5
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• pp.386-391
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• 1992

Background: Recently, bronchial provocation of the airway of atopic asthmatic subjects with inhaled allergen has been shown to produce an initial peripheral blood eosinopenia followed by an eosinophilia occurring approximately 12 to 18 hrs after the challenge. However there are few studies about the change of peripheral eosinophil count (PEC) after bronchial provocation with nonspecific stimuli such as histamine or methacholine. Interestingly our preliminary study demonstrated a notable change of PEC during bronhial provocation with inhaled histamine in some asthmatic subjects. This study was designed to reevaluate our preliminary data and to further investigate the change of PEC during as well as after bronchial provocation with inhaled histamine in bronchial asthma tics. Methods: Sixteen asthmatic subjects participated in this study. Bronchial provocation with inhaled histamine was done between 9 AM and 12 MD. Blood samplings for PEC were done with 5 minutes intervals during the procedure, and repeated at 1 hour, 2 hours, 4 hours, 8 hours, 24 hours, and 48 hours after the procedure. Results: The results were as follows; 1) The patients were divided into two groups characterized by each pattern in the change of PEC during the procedure. A group (11 of sixten, group I) showed an increasing pattern of PEC and another group (5 of sixteen, group II) showed a decreasing pattern of PEC during the procedure. 2) Group I demonstrated a tendency to maintain continuously higher level of PEC than the baseline value until 48 hours after the procedure. 3) Group II demonstrated a tendency to maintain continuously lower level of PEC than the baseline value until 48 hours after the procedure. 4) There were no significant differences in their clinical parameters including baseline eosinophil count, baseline $FEV_1$, $PC_{20}$ of histamine, and serum IgE level between group I and group II. Conclusion: Our results suggest that the change of PEC produced by inhaled histamine in asthmatic subjects is much different from that produced by inhaled allergen, and that each patient may have their individual characteristics in the change of PEC in response to bronchial provocation with inhaled histamine. Alternatively these findings suggest that eosinophils may be partially involved in the early asthmatic reaction.

• Journal of the Korean earth science society
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• v.40 no.6
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• pp.572-583
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• 2019

In this study, the atmospheric vertical structure (AVS) associated with summertime (June, July, and August) heavy rainfall in Seoul was classified into three patterns (Loaded Gun: L, Inverted V: IV, and Thin Tube: TT) using rawinsonde soundings launched at Osan from 2009 to 2018. The characteristics of classified AVS and precipitation property were analyzed. Occurrence frequencies in each type were 34.7% (TT-type), 20.4% (IV-type), 20.4% (LG-type), and 24.5% (Other-type), respectively. The mean value of Convective Available Potential Energy (1131.1 J kg^-1) for LG-types and Storm Relative Helicity (357.6 ㎡s^-2) for TT-types was about 2 times higher than that of other types, which seems to be the difference in the mechanism of convection at the low level atmosphere. The composited synoptic fields in all cases showed a pattern that warm and humid southwesterly wind flows into the Korean Peninsula. In the cases of TT-type, the low pressure center (at 850 hPa) was followed by the trough in upper-level (at 500 hPa) as the typical pattern of a low pressure deepening. The TT-type was strongly influenced by the low level jet (at 850 hPa), showing a pattern of connecting the upper- and low-level jets. The result of analysis indicated that precipitation was intensified in the first half of all types. IV-type precipitation induced by thermal instability tended to last for a short term period with strong precipitation intensity, while TT-type by mechanical instability showed weak precipitation over a long term period.

• Journal of the Korean Institute of Landscape Architecture
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• v.39 no.4
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• pp.74-82
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• 2011

During the industrialization and urbanization of the country, urban rivers have been covered over and developed without forethought and thus became estranged from spaces utilized by area residents in everyday life. Recently, an influx of people and uses have increased largely because accessibility improved through restoration projects which have transformed these river areas into pleasant environments. It thus appears that these projects have an impact on community consciousness for area residents who live near the restored rivers to some extent. The purpose of this study was to determine via questionnaire the effects and influences of urban river restoration on area residents targeting visitors to Seongnaecheon(stream), Songpa-gu, Seoul, which has been restored recently. Factors in the questionnaire analysis included such items as the use status of Seongnaecheon, community consciousness(feeling of belonging, solidarity, feeling settled), and a before and after comparison of the restoration(change of consciousness, regional effects), etc. According to the results of analysis, visitors who have utilized the stream more than 1~2 times per week after the restoration project accounted for the greatest portion. The main purposes of these visits were to 'rest' and 'exercise' while the ratio of using it as a 'meeting space with neighbors and strangers' was low. Community consciousness of area residents using Seongnaecheon was generally high. As a result of an analysis of consciousness differences between groups after dividing visitors into 3 groups according to the frequency of visits, there were significant differences in the consciousness level between groups with high community consciousness levels in visitors who visited frequently. In consideration of these results, the provision of programs along with proper facilities that can be used is deemed important for area residents so as to inspire community consciousness of the area by means of activating both community activities and the progressive use of the restored river.

• Clinical and Experimental Pediatrics
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• v.46 no.5
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• pp.484-489
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• 2003

Purpose : To understand morphologic and hemodynamic variations in patients with pulmonary atresia with intact ventricular septum(PA/IVS), and to decide the best treatment modalities, we measured right ventricular volume, inflow, and outflow valvular annulus size in these patients and compared them with those of normal newborns. Methods : Eight patients with PA/IVS diagnosed by echocardiography from January to December 2001 were enrolled in this study. Among the total eight patients, five were male and three were female. The mean age of patients was 6.9 days(1-34 days), and the mean body weight was 3,343 gm (2,970-4,000 gm). Ten fullterm newborn infants with sepsis or hyperbilirubinemia without heart disease were enrolled as a control group. Echocardiographic and Doppler studies using Acuson Aspen (7Mh probe) were recorded on super-VHS videotape and later on, with review mode. We measured volumes of right and left ventricles, aortic, pulmonic, mitral and tricuspid valvular annulus sizes using an installed program, and then these parameters were compared with those of the control group. Results : Mean Z-value of tricuspid valvular annulus in PA/IVS was $-3.69{\pm}2.80$(-8.4--0.45), and tricuspid/mitral valvular annulus size ratio $0.68{\pm}0.15$(0.43--0.84). The more the tricuspid/mitral valvular annulus size ratio, the more Z-value of tricuspid valvular annulus(P=0.003, r=0.885). Those patients who underwent pulmonary valvuloplasty(balloon or surgical) had a tendency toward larger volume of the right ventricle, more Z-value of pulmonic and tricuspid valvular annulus, and more tricuspid/mitral valvular annulus size ratio than those patients who underwent a shunt operation. Conclusion : Compared to a measurement of the volume of the right ventricle, measurements of tricuspid/mitral valvular annulus size ratio and Z-value of tricuspid valvular annulus may be easier and better parameters to decide the treatment method and to predict prognosis in PA/IVS patients.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.97-102
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• 2001

Cheju island depends on a hydrogeologically vulnerable aquifer system as its principle source of drinking water. Most of golf courses are located in the area which is important for the ground water recharge, and pesticides are applied to golf courses often at relatively high rates. Therefore, turf pesticides in golf course should be applied without adversely impacting ground water. In this experiment, downward movement of pesticides was monitored in model greens of golf course, where different adsorbents were layered in 3-cm thickness at 35-cm depth, and effect of the adsorption layer on the leaching loss of pesticides was investigated. Major leachings were observed in the periods of heavy rain and very limited leaching was observed under artificial irrigation. Fenitrothion and triadimefon, which have relatively short persistence and high adsorption coefficient, were found in the leachate in low concentrations only at the first rainfall event, around 20 days after the pesticide application. However, diniconazole, which has a relatively long half-life (97 days), was detected in the leachate during the whole period of experiment and concentration was much higher than those of the other pesticides. Maximum leachate concentrations were 1.9, 10.3, and 84.5 ${\mu}l^{-1}$ for fenitrothion, triadimefon, and diniconazole, respectively. Therefore, in golf course green which allows rapid water percolation and has extremely low adsorption capacity, persistence in soil could be more important factor in determination of leaching potential of pesticides. Total quantity of pesticides leached from the model green was <0.2% for fenitrothion and triadimefon and 1.8% for diniconazole. Adsorption layers significantly reduced pesticide leaching, and active carbon and Orpar were more effective than zeolite. In the model green having adsorption layer of active carbon or Orpar, leaching loss of pesticides was reduced below 0.01% of the initial application.

• Journal of the Korea Organic Resources Recycling Association
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• v.22 no.4
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• pp.21-27
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• 2014

Pig slurry has been considered as environmental waste to be treated in an appropriate manner. Moreover, water-born pollution loads by agricultural non-point source(NPS) pollution are expected to become intensified due to ongoing precipitation change. This study was conducted to develop a best management practice to reduce NPS pollution load by agricultural activity with pig manure compost. An eco-friendly way, small drainage pond, was suggested in this study to avoid direct drainage of agricultural runoffs and eventually reduce the amount of pollutants discharged into the surrounding aqua-environment. A small pond($12m^2$) was constructed at the corner of a rice paddy field($17,15m^2$) located in Suwon, Korea. Water was allowed to drain only via a small drainage pond. Sampling was repeatedly made at two locations, one from an entrance and the other from an exit of a pond, during the rice cultivation period(May to October, 2013). Generally, sampling was made only when runoff water drained through a pond, such as during and/or after rain(irrigation). The water quality analysis showed that all quality parameters(SS, $COD_{Mn}$, T-N, and T-P) were improved as water passed through the pond. The amount of runoff water was reduced by 67.8%. Suspended solids and $COD_{Mn}$ concentrations were reduced by 79.8% and 71.9%, respectively. In case of T-N and T-P amounts, the reduction rates were 73.6% and 74.9%, respectively. Our data implies that agricultural NPS pollution from rice paddy fields with pig manure-based fertilizer can be effectively managed when an appropriate drainage water management practice is imposed.