• Journal of Korean Society of Environmental Engineers
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• v.39 no.7
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• pp.377-384
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• 2017

This study examined the possibility of solving the water shortage problem through the water reuse of buildings through the Suwon water reuse (greywater) facility installation project conducted as a pilot project of Ministry of Environment. Water reuse of individual building units can reduce city water demand by up to 25%. This is a level that can solve the water shortage problem in Korea. However, in order to revitalize the water reuse facilities of individual buildings, it is necessary to solve the problem of the user's rejection of the greywater and the economical problems. The resolution of the user's rejection can be solved by linking the MBR process with the AOP process. When the MBR process and the AOP process are operated in conjunction with each other, it is found that the users do not feel the water quality difference with the tap water. Economical problems can be solved at the water rate levels when the facility capacity is over 100 ton/day considering the construction cost and the operation cost, and when the operation cost alone is over 15 ton/day. Furthermore, when considering the social benefit cost, it is found that profit is generated from 150 ton/day.

• The Korean Journal of Pesticide Science
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• v.12 no.1
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• pp.24-33
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• 2008

In this study, the mobility of seven pesticides from soil in different slopes was investigated by simulated rainfall under field conditions. Simulated rainfall subjected to $22\;mm\;hr^{-1}$ was treated using rainfall simulator after 12 hr of pesticide treatment. Amounts of the pesticides were measured in run-off water samples. The soil samples collected before and after rainfall from upper, middle and lower parts and three different depths of sloped-plot were also analyzed. At result, the order of the amount of pesticide residues was $0{\sim}15$ > $15{\sim}30$ > $30{\sim}45\;cm$ of soil depth and no pattern was shown in upper, middle and lower, and different slopes in soil samples. all pesticides from the run-off water samples collected from soils were detected maximum 96% within 60 minutes after first collection except carbendazim and cypermethrin which have the lowest water solubilities. These results revealed that mobility of pesticides can be dependant mainly on soil textures and physicochemical properties of pesticides. Therefore, it can be suggested that selection of pesticides should be considered for properties of pesticide in the alpine and sloped-land.

• Journal of Korean Society of Environmental Engineers
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• v.36 no.11
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• pp.781-790
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• 2014

Contaminants such as organic matters, nutrients and toxic chemicals in rivers and lakes with a weak flow rate are first removed from the water and accumulated in the sediments. Subsequently, they are released into the water column again, posing direct/indirect adverse effects on the water quality and aquatic ecosystems. In particular, phosphorus is known to accelerate the eutrophication phenomenon when it is released into the water column via physical disturbance and biological/chemical actions as one of important materials that determine the primary production of aquatic ecosystems and an element that is stored mainly in the sediments in the process of material circulation in the body of water. In this study, the effect on reducing phosphorus release in sediments was analyzed by applying different capping materials to lake water, where the effect of aquatic microorganisms is taken into account, and to distilled water, where the effect of microorganisms is excluded. The experimental results showed that capping with chemical materials such as Fe-gypsum and $SiO_2$-gypsum further reduced the phosphorus release by at least 40% compared to the control case. Composite materials like granule gypsum+Sand showed over 50% phosphorus release reduction effect. Therefore, it is determined that capping with chemical materials such as granule-gypsum and eco-friendly materials such as sand is effective in reducing phosphorus release. The changes in phosphorus properties in the sediments before and after capping treatment showed that gypsum input helped to change the phosphorus that is present in lake sediments into apatite-P, a stable form that makes phosphorus release difficult. Based on the above results, it is expected that the application of capping technology will contribute to improving the efficiency of reducing phosphorus release that occurs in river and lake sediments.

• Economic and Environmental Geology
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• v.36 no.5
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• pp.339-347
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• 2003

Using 171 groundwater chemistry data, seawater intrusion in the Ulsan area was studied. The area near the downstream area of the Taehwa River shows the higher Cl concentrations(11,300 mg/L in maximum), whereas the Cl concentrations are generally low in the eastern coastal area maybe due to the geology of the area. When Cl concentrations are very low, groundwater shows Br:Cl weight ratios significantly deviating from the Br:Cl ratio of seawater($34.7{\times}10^{-4}$). However, Br:Cl ratios are very close to the value of seawater when Cl concentrations are higher than 100 mg/L. Eleven groundwater samples having very high Cl concentrations(>500 mg/L) show that ionic ratios for Ca, Mg, $SO_4$, $HCO_3$ and $SiO_2$ are considerably different from those of seawater. This indicates that the origin of the high Cl groundwaters occurring along the Taehwa River are likely to be the residual salines from the salterns previously located on the alluviums rather than the seawaters intruded recently. These waters seem to be accumulated in the sediments before the drastic expansion of the city. Considering the characteristics of the urban groundwater system where the inflow exceeds the outflow, it is anticipated that the high Cl concentration in the groundwater show a decreasing trend in the future.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1993.04a
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• pp.146-146
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• 1993

신장에서 브라디키닌(Bradikinin, BK)의 생리적 역할을 규명하기 위한 첫 단계로 토끼신장 근위세뇨관의 일차배양세포를 이용, BK 수용체를 ($^3$H) BK를 이용하여 수용체결합실험을 함과 아울러 세포배양과정에서 여러 성장인자들의 BK 수용체발현에 미치는 영향을 관찰하였다. 첫째, 토끼 신장의 피질, 수질 및 근 위세뇨관 둥 각 부위에 대한 BK 수용체결합 실험결과 신수질 부분에 가장 많은 BK 수용체가 발견되었으며 이때 해리항수는 0.52 nM, 그리고 최대결합부위는 mg 단배질당 112.5 fmol이었다. 둘째, serum free 배지에서 insulin, transferrin 그리고 hydrocortisone이 성장인자로 사용될 때 BK 수용체발현이 가장 높았으며 이 중 인슐린에 가장 큰 영향을 받았다. 한편 인슐린의 최적농도를 결정하는 실험의 결과 5 $\mu\textrm{g}$/ml매서 가장 높은 수용체발현을 나타내었으며 그 이상에서는 별다른 차이를 보이지 못했다. 세째, 위의 세 성장인자에 prostaglandin E$_1$이나 triiodothyronine을 첨가시 BK 수용체발현은 오히려 저하되었다. 네째, fetal bovine serum (FBS)과 위의 세 성장인자간의 수용체발현능을 비교한 실험에서 세포배양 후 첫 일주일에는 FBS가 세 성장인자보다 약간 나은 수용체발현능을 나타내었으나 그후 이주째에는 세 성장인자가 BK 수용체발현에 더 적절한 요소임을 보여주었다. 이상의 결과로 보아 토끼 근위세뇨관 상피세포에서의 BK 수용체발현은 세포성장인자로 insulin, transferrin, hydrocortisone 중 insulin에 가장 큰 영향을 받는것으로 보이며, 이들 세가지 성장인자는 serum free 배지에서 세포성장 및 기능에 많은 영향을 주는 것으로 생각된다.prolidine이 $K_{M}$ /K$_{H}$ 비가 가장 높았고 diphenidol이 가장 낮았다. 이상의 결과로 보아 항 histamine제의 muscarinic receptor 차단작용은 이들 약물의 항 alleragy 효과에 필요한 작용이 아니며 본 실험에서 추정된 항 histamine제의 H$_1$-receptor와 muscarinic receptor에 대한 상대적 역가는 이들 약물의 선택과 평가에 중요한 지표가 될수 있을 것으로 생각된다.ing ischemic insults. The nature of the receptor is being explored by molecular genetic techniques, and we have recently cloned two of the major subunits; some of the data will be presented.LIFO, 우선 순위 방식등을 선택할 수 있도록 확장하였다. SIMPLE는 자료구조 및 프로그램이 공개되어 있으므로 프로그래머가 원하는 기능을 쉽게 추가할 수 있는 장점도 있다. 아울러 SMPLE에서 새로이 추가된 자료구조와 함수 및 설비제어 방식등을 활용하여 실제 중형급 시스템에 대한 시뮬레이션 구현과 시스템 분석의 예를 보인다._3$", chain segment, with the activation energy of carriers from the shallow trap with 0.4[eV], in he amorphous regions.의 증발산율은 우기의 기상자료를 이용하여 구한 결과 0.05 - 0.10 mm/hr 의 범위로서 이로 인한 강우손실량은 큰 의미가 없음을 알았다.재발이 나타난 3례의 환자를 제외한 9례 (75%)에서는 현재까지 재발소견을 보이지 않고 있다. 이러한 결과는 다른 보고자들과 유사한 결과를

• Journal of Korean Society of Environmental Engineers
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• v.34 no.9
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• pp.637-643
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• 2012

This study was carried out to investigate how reversible and irreversible fouling were distributed in the filtration using ceramic membrane of 300 kDa pore size for secondary effluent of wastewater. It was performed by calculating fouling as numerical method for diverse TMPs and measured F-EEM and SEC for raw water, treated water and backwashed water. Water quality was also checked to know whether treated water quality was stable or not. The results showed that reversible fouling formation was increased when lower TMP was applied and it is caused by protein like organic matters having higher molecular weights. The secondary wastewater effluent had diverse molecular weight materials, especially contaminants lower than 0.5 kDa and bigger than 12 kDa. Decreasing TMP induced contaminants above 12 kDa and below 1 kDa to become reversible fouling.

• The Korean Journal of Pesticide Science
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• v.9 no.4
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• pp.411-421
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• 2005

This study was carried out to establish rational methodologies for the use of pesticide formulations to be sprayed after water-dilution. Hardness and electric conductivity of six major river water and ground water sampled from 52 sites in major rice-growing areas across the country ranged from 5 to 324 ppm(av. 90 ppm) and from 0.038 to 1.078 dS/m(av. 0.265 dS/m), respectively, which are acceptable for diluent water of pesticides. The pH changes in pesticide spray solutions with time after preparation mainly depended on the pH of the water used for pesticide dilution. The surface tensions of pesticide spray solutions reduced slightly with time after preparation, irrespective of kinds of pesticide formulations. Suspensibility of WPs became worse with an increase in the hardness and salt concentrations of diluent water, even though the degree was negligible. Emulsion stability of ECs became worse with an increase in hardness and salt concentrations of diluent water. Degradation rates of the active ingredients of pesticide spray solutions 3 days after preparation were less than 5%, regardless of mixing or non-mixing of two or more pesticides. Consequently, the spray solutions of most pesticides were usable until two to three days after preparation unless physical properties deteriorated. The tank-mixing order of EC and WP formulations did not make any differences in all the physical properties of pesticide spray solutions. However, the proper order for the tank-mixing of compatible pesticides was WP, WG, SC, EC, and SL, because the order is easy to prepare the pesticide spray solutions. The efficacy of pesticide spray solutions on the respective target pathogens and insect pests of rice plants three days after preparation was recorded over 95% of that of 0 day, which was almost the same as that of the solutions applied punctually after preparation.

• Korean Journal of Ecology and Environment
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• v.52 no.2
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• pp.81-93
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• 2019

Phytoplankton is one of the important primary producers providing organic matter through photosynthesis in aquatic environments. In order to determine a temporal and spatial variation in primary productivity after weir construction in the Nakdong River, we investigated carbon uptake rates using in-situ $^{13}C$ labeling experiments and identified algal communities contributing to primary productivity using HPLC-CHEMTAX analysis from October to December, 2017. The primary productivity gradually decreased from fall to early winter season ($249{\sim}933mgC\;m^{-2}d^{-1}$ in October, $64{\sim}536mgC\;m^{-2}d^{-1}$ in November and $60{\sim}274mgC\;m^{-2}d^{-1}$ in December, respectively). This is attributed to the temporally declining light intensity and the decreasing biomass and physiological activity of phytoplankton in winter. The contribution of diatoms to the phytoplankton community in the Nakdong River was approximately 63% at all the sampling sites and seasons, while the contribution of cryptophytes increased from 9% in October to 32% in November and December. The temporal changes in the primary productivity and the dominant phytoplankton species in the mid and downstream weirs of the Nakdong River was investigated for the first time, after construction of the weirs, and major environmental factors controlling the temporal variation in primary productivity and phytoplankton communities were identified in this study. We suggest that seasonal field investigations will provide further information on the major environmental factors which affect the annual variation of primary productivity and phytoplankton communities.

• Economic and Environmental Geology
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• v.53 no.6
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• pp.655-666
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• 2020

This study evaluated the characteristics of arsenic production in groundwater through microbial community analysis of groundwater contaminated with high arsenic in Haman area. Groundwater in Haman area is contaminated with arsenic in the range of 0-757.2 ㎍/L, which represents the highest arsenic contamination concentration reported in Korea as natural groundwater pollution source. Of the total 200 samples, 29 samples (14.5%) showed higher arsenic concentration than that of 10 ㎍/L, which is the standard for drinking water quality, and 8 samples (4%) found in wells with 80-100 m depth were above 50 ㎍/L. In addition, seven wells with arsenic concentration more than 100 ㎍/L located in the northern part of Haman. As a result of microbial community analysis for high arsenic-contaminated groundwater, the microbial community compositions were significantly different between each sample, and Proteobacteria was the most dominant phyla with an average of 61.5%. At the genus level, the Gallinonella genus was predominant with about 12.8% proportion, followed by the Acinetobacter and Methermicoccus genus with about 7.8 and 7.3%, respectively. It is expected that high arsenic groundwater in the study area was caused by a complex reaction of geochemical characteristics and biogeochemical processes. Therefore, it is expected that the constructed information on geochemical characteristics and microbial communities through this study could be used to identify the origin of high arsenic groundwater and the development of its controlling technology.

• Korean Journal of Environmental Biology
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• v.29 no.4
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• pp.296-304
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• 2011

This study was carried out to investigate the relation between water quality and structure of the aquatic ecosystem in the Lake Gachang from February to December in 2010. The annual mean COD (Chemical Oxygen Demand) in Lake Gachang was 3.5 mg $L^{-1}$, indicating, level II of environmental standards and the trophic state was mesotrophic. The seasonal succession of phytoplankton showed that Bacillariophyceae was mostly dominant species throughout the year except August. In case of zooplankton, rotifers dominate in the most seasons, but copepod (Nauplii) in August. The macrophyte plants showed diverse species composition consisted of 9 varieties, 77 species, 64 genera, 34 families and 24 orders. Surveyed species of macroinvertebrates were classified into 1 phyla, 2 classes, 4 orders, 7 families, 9 species. The macroinvertebrates showed FFG (Functional Feeding Groups) such as GC (Gathering-Collector) and SH (Shedder). A total of 42 species of fish was collected including $Zacco$ $koreanus$ and $Coreoperca$ $herzi$. In this study, we investigated environmental factors including pollutant source, load, water quality and distribution characteristics of biota such as phytoplankton, zooplankton, macrophyte plants, macroinvertebrates, fish.