• The Korean Journal of Ecology
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• v.27 no.6 s.122
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• pp.375-381
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• 2004

We investigate the biological treatment of processed-leachate from SUDOKWON landfill site in Korea by the reed (Phragmites australis)-bed with a continuous flow system. The reed individuals showing superior growth in processed-leachate experiment were selected among the reeds of thirteen natural habitats by means of the comparisons between the removal rates of nutrient salts, eco-physiological responses and growth. The reed-beds (combination of the reed individuals showing superior growth with helper microorganisms) were continuously supplied with processed-leachate. We monitored the effluents that passing through the reed-beds during the experiment period. After five weeks, analysis results of effluent from each reed-bed were as follows; chromaticity, total nitrogen, total phosphorus, biological oxygen demand, chemical oxygen demand, total dissolved solid and salinity decreased $29.5{\sim}36.9\%,\;49.4{\sim}67.2\%,\;42.1{\sim}94.6\%,\;74.5{\sim}88.8\%,\;15.6{\sim}20.8\%,\;17.5{\sim}35.4\%\;and\;15.3{\sim}34.7\%$, respectively. These results represented the substantial improvement of water-quality after passing through reed-bed in a continuous flow system.

• Journal of Aquaculture
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• v.13 no.1
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• pp.87-99
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• 2000

Field survey on the variational characteristics of water quality and chlorophyll a concentraion were carried out at the 25 stations for four seasons in Kogum-sudo(Straits) southern coast of Korean Peninsula from Feburuary to October in 1993. We made an analysis on biological factor as chlorophyll a concentraion as well as physicio-chemical factors such as water temperature salinity sigma-t transparency dissolved oxygen(DO) chemical oxygen demand(COD) nutrients (ammonia, nitrite, nitrate, phosphate, and silicate) N/P ratio and suspended solid(SS). The waters in the Kogum-sudo were not stratified due to the tidal mixing. And the high productivity in photic layer were supported by high nutrients concentration from bottom waters. The high concen-trations of suspended solid in straits had a bad influence upon marine biology of nature and cultivations. In Kogum-sudo had a sufficient nutrients for primary productivity during a year. Especially phosphate and inorganic nitrogen were high the other side silicate was very low. The source of nutrients supply depend on rather mineralization of organic matters and input of seawater from outside than input of freshwaters from lands. Phytoplankton biomass as measured by chlorphyll a concentratiion was very high all the year round and it was controlled by the combination o f several environmental factors especially of phosphate in summer and dissolved nitrogen in other seasons.

• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.420-431
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• 2010

Simple material budget models were developed to predict the dry season water quality for a river-type reservoir in Paldang, Republic of Korea. Of specific interest were the total phosphorus (TP), chlorophyll ${\alpha}$ (Chl. ${\alpha}$), 5-day biochemical oxygen demand (BOD), and chemical oxygen demand (COD). The models fit quite well with field data collected for 20 years and have enabled the identification of the origins of organic materials in the reservoir. The critical hydraulic load that determines the usability of phosphorus for algal production appeared to be about $1.5m\;d^{-1}$. When a hydraulic load was smaller than the critical value, the concentrations of $Chl.{\alpha}$, COD, and BOD in the reservoir water became sensitive to internal algal reactions such as growth, degradation, and settling. In spite of the recent intensive efforts for organic pollutant removal from major point sources by central and local governments, the water quality in the reservoir had not been improved. Instead, the concentration of COD increased. The model analysis indicated that this finding could be attributed to the continuing increase of the algal production in the reservoir and the allochthonous load from non-point sources. In particular, the concentrations of COD and BOD of algal origin during 2000~2007, each of which is comprised of approximately one half of the total, were approximately 2.5 times higher than those observed during 1988~1994 and approximately 1.3 times higher than those between 1995~1999. The results of this study suggested that it is necessary to reduce the algal bloom so as to improve the water quality of the reservoir.

• The Journal of the Korea Contents Association
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• v.6 no.10
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• pp.1-8
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• 2006

The new system evaluating the pollution of the water quality for the branches of geum river using the fuzzy integral was proposed in this study. In this paper, the five individual factors, such as BOD(biochemical oxygen demand), COD(chemical oxygen demand), SS(suspended solids), T-N(total nitrogen), and T-P(total phosphorus) are selected. The measurement of fuzzy integral was determined depending on the degree of how they affect the pollution of water quality. The real values for the five factors measured and obtained from the branches of the geum river was normalized to ranging from 0 to 1. Finally, using the fuzzy integral, the degree of the pollution for the branches of geum river was expressed as the real numerical number. As a result, it appears that this approach can be proposed as the new system evaluating the pollution of the water quality for the branches of the geum river.

• Clean Technology
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• v.19 no.3
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• pp.295-299
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• 2013

This study was purposed and performed to evaluate removal efficiency of non-point source pollution in the process and system based on bio-retention design criteria regulated by EPA. Basic Column Reactors (BCR) were prepared for optimal determinations of inflow rate of first rainfall runoff and composition and ratio of soil layers. Removal efficiencies of non-point source pollution from synthetic runoff and real first rainfall runoff, directly sampled from motor way and parking lot, were analyzed, respectively. Removal efficiency of SS, BOD, COD, T-N, and T-P were all shown to be more than 80%.

• Journal of the Korean Geographical Society
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• v.39 no.4
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• pp.544-561
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• 2004

Weekly monitoring of discharge and water quality in forested and agricultural subcatchments were performed to understand the difference of water quality caused by land uses in Doegwollyong area. Correlations between water quality variables including discharge were analyzed for the same purpose. There was little variation of water Quality in forested subcatchment. On the other hand, the range of water quality variation in agricultural subcatchment was wide due to soil loss and the application of chemical fertilizers and livestock manure. Dissolved oxygen(DO) had strong negative correlation with discharge in both subcatchments. Total nitrogen(T-N) and potassium ion(K$^{+}$) had stronger positive correlation with discharge in forested subacatchment than in agricultural one. On the other hand, total suspended sediments(TSS), total phosphorus(T-P), and chemical oxygen demand(COD) had stronger correlation with discharge in agricultural subcatchment than in forested one. As water pollution of the Doam Lake, especially the increase of T-P is serious, soil conservation is very important to improve water quality. In particular, the loss of soil and nutrients from late June till early July were more serious than any other seasons, therefore it is necessary to apply environmentally sustainable methods of cultivation.n.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.297-300
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• 2001

최근의 컴퓨팅 환경은 이질적인 클라이언트와 서버들간의 상호 운용성을 요구하는 분산 어플리케이션을 위한 프로그래밍 파라다임을 지원하기 위한 분산 객체 컴퓨팅 환경으로 발전되고 있다. 여기에는 복잡한 네트워킹과 다양한 멀티미디어 응용 서비스를 위한 객체지향 기술들이 접목되고 있다. 이러한 분산 컴퓨팅 환경에서 처리되는 어플리케이션들의 실시간 서비스 지원을 위해 요구되는 실시간 특성과 분산 객체들의 관리의 어려움을 해결하기 위하여 본 논문에서는 실시간 객체그룹 플랫폼을 구축한다. 기존의 연구들은 실시간 CORBA를 사용하거나 또는 ORB를 수정하거나 실시간 운영체제상에 특정 CORBA 제품군을 사용하여 분산 환경의 특정 영역의 성능향상만을 도모하고 있다. 그러므로, 본 논문은 ORB의 수정 없이 표준 CORBA상에서 실시간 특성을 지원한 수 있는 실시간 객체그룹 플랫폼을 설계한다. 본 논문의 실시간 객체그룹 구조는 객체들의 관리적인 측면과 실시간 어플리케이션 서비스 지원 측면에 대한 요구사항들을 분석하여 정립한 모델이며, 구성요소들의 기능을 관리와 서비스로 분리하여 각각의 기능수행시에 발생하는 객체간의 상호작용이 다른 기능에 영향을 미치지 않도록 한다. 또한, 구축된 플랫폼은 실시간 어플리케이션 개발자에게 실시간 특성 파라미터의 표현과 처리에 대한 투명성을 부여하여 어플리케이션에 유연성과 확장성을 제공하기가 용이하도록 한다. 따라서, 본 논문은 실시간 객체그룹 플랫폼의 구성요소들에 대한 역할을 정의하고 기능을 정립하며, 각 구성요소들을 설계하고 구현하였으며, 구현되어진 실시간 객체그룹 플랫폼의 기능과 수행 성능을 검증한다.가지 유기화합물 중에서는 35.6%를 차지하였다. BTEX 각각 개별물질은 미국 환경보호청이 제시하는 일일 노출 기준량(Reference Concentration; RfC) 보다는 현저히 낮았다. 총 휘발성 유기화합물읜 농도는 실내가 실외 보다 높았다(I/O ratio 2.5). BTEX의 상대적 함량도 실내가 실외보다 높아 실내에도 발생원이 있음을 암시하고 있다. 자료 분석결과 유치원 실내의 벤젠은 실외로부터 유입되고 있었고, 톨루엔, 에틸벤젠, 크실렌은 실외뿐 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타

• Current Research on Agriculture and Life Sciences
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• v.16
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• pp.75-83
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• 1998

The purpose of this survey was to investigate the regional and seasonal characteristics of a water system and to obtain basic information of a water system at Andong bridge, Nakdan bridge, Kangjung, Waekwan bridge and Koryung bridge along Nakdong River. We surveyed the water quality in the Nakdong River for 2 years from Jan. 1996 to Dec. 1997. The results summarized were follows; 1) The pH in the Nakdong River on the basic of 2 years average were 6.5-8.6. 2) The DO, the COD and the BOD were low level in summer and high level in winter, respectively. 3) The suspended solids(SS) contents was high especially in summer. 4) The T-P and the T-N contents were higher than the lower level of nitrogen and phosphorous for algae growth and the contents were high especially in winter. 5) The $NH_4{^+}$-N and $NO_3{^-}$-N were also observed to be quite high.

• Journal of Navigation and Port Research
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• v.35 no.3
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• pp.259-263
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• 2011

This study explores ways to improve the actual conditions of ocean environment by conducting a comparative study on the current sea-water quality of Busan Metropolitan City and Incheon Metropolitan City that are representative sea port cities in Korea. The indices used to evaluate the sea-water quality include water temperature, salt content, PH, DO, COD, DIN, T-N, DIP, T-P, Sio2-Si, floating materials, and Chi-a. The findings of the analysis can be summarized as follows: First, ocean environmental states of Busan Metropolitan City and Incheon Metropolitan City are getting increasingly worse between the year of 2000 and 2003. Second, T-N, DIP and T-P have been main contributors in worsening ocean environmental states of Busan Metropolitan City and Incheon Metropolitan City.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.24 no.3
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• pp.97-106
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• 2018

This study aimed at examining the suitability of $Tenax^{(R)}$ for the migration testing of food packaging materials, which is currently approved in the EU as a dry food simulant. The results are used as a basis to examine the feasibility of introducing $Tenax^{(R)}$ to Korean regulation. The OMVs of test specimen into various solvents (diethyl ether, ethanol, pentane, and acetone) after exposure to $100^{\circ}C$ for 1 hr were compared. Diethyl ether showed the highest OMV ($1.33mg/dm^2$) among the solvents tested. When the tests were conducted with different amounts of $Tenax^{(R)}$ of 2, 4, or 8 g per specimen, the OMVs were 0.75, 1.33 and $1.40mg/dm^2$, respectively. The OMV obtained with a closed system after wrapping with aluminum foil showed a significantly higher OMV ($1.61mg/dm^2$) than that without aluminum wrapping ($1.318mg/dm^2w$) and an open system without lid ($1.06mg/dm^2$). The specific migration rates of surrogates spiked in the polyethylene test film and paper samples into $Tenax^{(R)}$ were compared with those into liquid food simulants including 95% ethanol and n-heptane, and actual foods such as starch, skim milk, and sugar. In general, the specific migration levels of surrogates into $Tenax^{(R)}$ were similar compared with n-heptane, however those were significantly higher than into actual foods. These results suggest that $Tenax^{(R)}$ may be used as a food simulant for the long-term preservation of dried foods and paper products. However, more studies need to be conducted to investigate the factors influencing the migration into $Tenax^{(R)}$, such as the types of foods and packaging materials tested, migration conditions, and surrogates properties etc.