• 한국산학기술학회논문지
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• 제12권1호
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• pp.545-551
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• 2011

최근 고품질의 수돗물에 대한 소비자의 요구가 상승함에 따라 상수도 배급수관의 내부 부식에 의한 수질악화 및 부식제어 연구에 대한 관심이 높아지고 있다. 이에 따라 노후 관 교체 사업을 대신하여 수질 관리를 위한 부식 제어 수단을 강구하지 않고서는 근본적인 문제 해결이 이루어질 수 없는 실정이다. 본 연구에서는 수질안정화 약품 주입에 의한 상수도관 내부 부식제어 효율을 평가하기 위해 Pilot Plant 실험을 실시하였으며, 부식성제어 효율은 물의 부식성을 나타내는 LSI(Langelier Saturation Index)값에 의해 평가되었다. 실험결과, Pilot Plant에 의해 제조된 반응수는 수질안정화 약품인 액상소석회($Ca(OH)_2$, liquid lime)의 주입으로 부식성이 개선되어 철 용출이 억제되는 효과가 확인되었다. 강관과 동관을 절단하여 제작한 시편의 부식도 측정을 통해 각각 35.4, 44.5%의 부식제어 효과가 있음을 확인하였고 수질안정화 약품이 주입된 Sample관이 더 두터운 부식 생성물 층을 갖고 있는 것으로 밝혀졌으며, 결과적으로 수질안정화 약품을 투입한 배관이 부식 방지 측면에서 안정한 수질을 갖고 있음을 알 수 있었다.

• 한국농공학회논문집
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• 제48권2호
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• pp.69-76
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• 2006

Fallow paddy areas have been increased due to the import of cheap agricultural product, and the unbalance between farming cost and rice price since 1990. The increasing fallow paddy area needs to be protected from the devastation by weed breeding for the re-cultivation. In this study, two fallow paddy fields managed with different water depth were selected for monitoring and analysing of water quality, water balance and plant body change. The managed fallow paddy fields were more effective in water quality purification and plants growth control than non-managed fallow paddy fields. And the fallow paddy field managed with some degree of water depth was the most effective field in terms of weed control.

• 한국환경복원기술학회지
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• 제4권4호
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• pp.72-81
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• 2001

This study is aimed to review the previous research accomplishments with analysis of problems and to suggest the counter plan for the watershed management and the ongoing research strategy. Phytoremediation provides a cost-effective techniques having a merit of low investment and maintenance cost. It could be one of the best techniques, which is an alternative plan to overcome economical situation and lack of experts in our country. In forest watershed affected by waste water and heavy metal pollutants should be controlled by vegetative remediation system, but the disposal techniques of harvested plant materials should be developed. Also, high degree areas of natural vegetation as a key model to recover the vegetation should be well conserved. It is important to restore forest continuity between upper stream and lower stream basin with the restoration of damaged in forest watershed. It is established to integrated protection system for land use and management plan and to natural environment evaluation methods affected by projects such as erosion control and developments in stream and forest. In addition, I suggest the continuous environmental monitoring system to treat the pollutions concerned.

• Nuclear Engineering and Technology
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• 제22권2호
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• pp.83-94
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• 1990

울진 1&2호기의 사용후 핵연료 중간저장을 위한 기존 저장조용량확장 방안으로서 maximum density rack (MDR)에 consolidated fuel을 저 장하여 현 9/3 노심에서 32/3으로 확장할 경우 방사능 농도가 적정기준 이하로 유지될 수 있는지 여부를 분석하였다. 이를 위해 본 연구에서는 정화계통의 연속적 운전방식과 주기적 운전방식에 대한 저장용수중의 방사능 농도계산을 위한 두 가지 계산 모델을 만들어 상호비교 하였다. 이 결과 두 경우 모두 32/3 노심저장에 대하여 기존 정화계통으로는 기준치인 5$\times$1-$^{-4}$ $\mu$Ci/ml이하로 유지시킬 수 없었다. 따라서 기존의 시설변경이 불가피하며 그 방안으로 사용후 핵연료 저장조에서의 양이온 탈염기 수를 증가시키는 방법이 타당한 것으로 나타났다.

• 펄프종이기술
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• 제46권5호
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• pp.79-87
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• 2014

The enrichment with nutrients in rivers and lakes becomes serious problems in Korea. As the environmental friendly solution, the phytoremediation are getting more attention and the water hyacinth could be a strong candidate plant for this. Water hyacinth is a free floating freshwater plant proven to be a effective plant used for a purification of a polluted lakes, sewage wastewater, and livestock wastewater. The biggest obstacles for application of water hyacinth in Korea could be the disposal of the water hyacinth before winter, because there is no feasible use for the water hyacinth until now. In this study, the characteristics of water hyacinth were deeply investigated for providing background data to develop appropriate application of the water hyacinth. The water hyacinth was fractioned three parts, leaf, air blader, root of which morphological properties were evaluated with microscope and field emission scanning electron microscope (FE-SEM). The water contents of each parts of the water hyacinth were 87% for leaf, 96.5% for air bladder, 94.6% for root. The chemical compositions of each parts were also measured and showed around 29% of hot water extract in leaf and air bladder, 42% holocellulose for leaf, 47% holocellulose for air bladder. The application of water hyacinth biomass without root parts to papermaking provided bulkier structure, but the tensile strength was decreased.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1175-1176
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• 2015

산업설비 중, 전력케이블은 설치 이후 적게는 수년에서 많게는 수십년에 걸쳐 진단없이 계속 사용 중에 있다. 인입케이블 경우, 한국전기안전공사에서 주기적으로 사업장 정기검사 시에만 DC내전압 시험을 실시하고 있으며 그 외에는 장시간 사용에도 불구하고 상태점검을 정확히 못 하고 있다. 본 연구에서는, DC내전압 시험 대신 현장에 적용되고 있는 VLF(Very Low Frequency) 진단방법에 대하여 수도사업장(취수장, 정수장 등)에서 사용 시, 진단방법 및 결과에 대한 신뢰성을 고찰하였다.

• Animal cells and systems
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• 제16권3호
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• pp.245-253
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• 2012

A genuine interstitial cyclopoid species belonging to the genus Psammophilocyclops Fryer, 1956 is recorded from the filtration basin of a water treatment plant, South Korea. The genus Psammophilocyclops is very rarely found, and only three species have been recognized as yet: P. boccaroi Fryer, 1956 from Africa, P. trispinosus Shen et Tai, 1964 and P. bispinosus Shen et Tai, 1964 from China. The present new species differs from the congeneric species by the character combination of 11-segmented antennule in female, four-segmented maxilliped with 2,1,1,2 setation, the spine formula of 3,3,3,3, and setal arrangement of 3,3,5,3 on the distal endopodal segments of legs 1-4. Descriptio and taxonomic accounts of the new species are presented with a revised generic diagnosis and a key to the species hitherto known in the genus.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2005년도 학술발표논문집
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• pp.485-489
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• 2005

Fallow paddy has been increased in disadvantageous farming condition area because of importation of foreign agricultural products, labor cost and the imbalance between farming cost and agricultural products price since 1990. The fallow paddy that has gradually increased needs to be prevented from the devastation by weed breeding for re-cultivation. In this study, two fallow paddies that manage with different water depth from the experimental field were selected for observation, and analysis of water quality, water balance and plant body change. The managed fallow paddy was more effective in water quality purification and plants growth control than non-managed fallow paddy. And the fallow paddy managed with a some degree water depth was the most effective field on weed control.

• 한국농공학회논문집
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• 제48권3호
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• pp.35-45
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• 2006

Fallow paddy areas have been increased due to the import of cheap agricultural product, and the unbalance between farming cost and rice price since 1990. In domestic, rice production control that decrease paddy field area has been introduced for the control of rice demand and supply and stabilization of rice price since 2003. Because of the desire of paddy field's owner to create benefit by using paddy for other object, fallow paddy would be continuously increased. In the other aspect, many people in the world is suffering from hunger because of the shortage of food. In case of Korea, continuous drought and flood damages will be potential concern of stable food supply. From this viewpoint, the increasing fallow paddy area needs to be protected from the devastation by weed breeding for the re-cultivation. In this study, fallow paddy managed with the shallow pools and shallows was selected fur monitoring and analyzing of water quality and plant body change. As the results, the managed fallow paddy found to be effective in the purification of water quality and the control of plant growth.

• 상하수도학회지
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• 제20권3호
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• pp.403-410
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• 2006

The objective of this study was to evaluate the possibility of sedimentation basin omission when installed hybrid membrane filtration process in the field plant with the capacity of $500m^3/day$ for 11 months in the "G", water purification plant in Seoul. In order to evaluate the possibility of the sedimentation basin omission, we measured the change of DOC by coagulant dosage. Dosage of PAC(power activated carbon) 4mg/L and coagulant($AI_2O_3$ 10%) 1.67mg/L were compatible to meet the water quality. Also according to the experiment without settlement process, optimization G values were determined to be 300/s, 64/s, and 32/s at the mixing tank, the first flocculator and the second flocculator, respectively. The test was performed under the conditions PAC-coagulation-no settlement-MF. As a result, a dosage of 4.0mg/L as PAC and 0.86 to 1.22mg/L as $Al_2O_3$(10%) in the condition of flux of 62.5LMH were determined to keep TMP value less than $1.0kg_f/cm^2$.