• 펄프종이기술
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• 제36권2호
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• pp.10-16
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• 2004

Structures and strengths of paper have been studied by analyzing fibers characteristics depending on refining methods. Mixing ratio of softwood and hardwood fibers and fibers characteristics have been analyzed for paper quality improvement. In this study flocculation and drainage of fibers were analyzed to improve the production efficiency and paper product's quality. Floc size and drainage rate depending on stock consistency and fines content were analyzed. Total amount of drainage during drainage process was measured quantitatively by using DI(drainage index). Floc size, viscosity of floc and dewatering times were also measured. In the case of refining load $2.8 kg_f$ , drainage was occurred by filtration mechanism rather than thickening mechanism because drainage resistance increased by fibrillation of fibers. Therefore, the drainage rate of $2.8 kg_f$ refining load stock was slower than that of $5.6 kg_f$.

• 한국수자원학회논문집
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• 제36권6호
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• pp.949-960
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• 2003

정상상태 가정을 완화시킨 습윤지수의 해상도 문제가 수치지형모형에서 다루어졌다. 반 동역학적 습은지수와 동력학적 습윤지수의 변화성을 수치고도모형의 격자 크기와 배수시간을 변화시키면서, 공간적 통계적으로 고찰하였다. 변화하는 배수시간과 격자크기에 따라 습윤지수의 구조화 양상이 관찰 되었다. 설마천 유역의 적용결과 비교적 짧은 배수시간에서는 습윤도의 천이성이 관찰되었고, 10,000 시간 이상의 배수 시간에서는 통계적 분석 결과가 정상상태의 특성으로 수렴함을 보여주고 있다. 반 동역학적 및 동역학적 습윤지수의 확률밀도 함수들은 계산결과의 안정성과 일관성에 관련이 있는 경계 격자 크기가 존재함을 보여주고 있다.

• 한국토양환경학회지
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• 제2권3호
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• pp.31-38
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• 1997

산성폐수에 함유된 오염물질의 물리적 화학적 특성이 배우 복잡하기 때문에 산성폐수에 의해 오염된 지표수나 지하수등의 오염정도를 지역적, 시간적 변화에 따라 비교하는 일은 쉽지가 않다. 본 논문에서는 산성폐수에 의해 오염된 지표수나 지하수의 오염도를 정량적으로 평가할 수 있는 수학적 지표를 제시하였으며, 오염지표를 이용하여 국내 폐탄광의 갱내 유출수에 대한 오염도를 검토하였다. 사용된 오염지표(Acid Mine Drainage Index)는 수질의 오염정도를 가장 잘 나타낼수 있는 7개의 변수 즉, pH값, 황산염(Sulfate), 철, 망간, 알루미늄, 구리 및 아연 함량을 이용하여 계산하였다. 사용된 변수는 오염도에 미치는 상대적인 중요도를 감안하여 가중치를 사용하였으며 , pH값 및 황산염함량에 가장 높은 가중치를 부여하였다. 국내 폐광산에서 유출되는 산성폐수의 오염도 평가결과 경북 문경에 소재한 석봉탄광이 조사탄광중 상대적으로 오염도가 높았으며, 지역적으로 영동지역에 위치한 폐탄광의 갱내 유출수가 영서, 중부, 서부 및 남부에 위치한 폐탄광에 비해 오염도가 높게 나타났다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 추계학술발표회
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• pp.382-385
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• 2003

QAMDI(Quantified Acid Mine Drainage Index) was developed for more synthesised, qualified and quantified assessment index which can be applied to both coal and metal mine drainage. QAMDI is calculated using three parameter groups i.e. acidity, sulfate contents and toxic metal contents. Since QAMDI expressed in terms of concentration. It reveals the different status of each mine drainage more clearly. QAMDI can be converted to the quantity of pollutant loading by being multiplied by the water flux.

• 펄프종이기술
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• 제42권1호
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• pp.48-53
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• 2010

Commercial micro pulps(Arbocel) were coated with three kinds of polymers using spray method. These coated micro pulps were used to papermaking additives to evaluate retention, drainage and physical properties of paper. The retention and drainage were improved with addition of polymer coated micro pulp. The bulk index of paper was also increased, but tensile and tear strength were decreased slightly, probably due to weakening of internal bonding. These results showed that the use of polymer coated micro pulp was an effective method to improve retention, drainage and bulk index of paper.

• 한국산학기술학회논문지
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• 제20권7호
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• pp.1-7
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• 2019

본 논문은 침수피해 방지를 위한 기존의 우수배제시스템의 한계점을 극복하기 위해서 신규 개발된 친환경 수로형 우수배제시스템을 비교 및 분석하고, 기존 시스템 대비 장점을 정량화하기 위한 통합평가지표의 개발 및 적용에 관한 연구이다. 이에 전과정평가(Life Cycle Assessment, LCA)의 개념을 적용하여 각 공정별 필요물량과 비용을 산정하여 비교하였고, 또한 탄소배출량을 각 과정별로 산정하여 고려하는 통합평가지표를 개발하여 각각의 기술에 적용하였다. 그 결과 원형 집수시스템에 비해 전 과정에 걸쳐 비용이 53 %, 측구 집수시스템에 비해 63 %가 절감되는 것으로 분석되었다. 또한 통합평가지표 적용결과, 기존 기술대비 수로형 집수시스템을 평가한 결과 건설공사 분야를 제외한 나머지 4가지 분야(건설자재, 운용 및 유지관리, 해체, 폐기)에 있어서 80 % 이상의 높은 점수로 평가되었다. 본 연구에서 개발된 평가지표를 경기도 안양현장과 인천 청라현장에 적용하여 기존 기술대비 약 35 ~ 100 % 개선된 높은 점수로 향상되어 개선효과를 입증하였고 동시에 적용성을 확보하였다.

• 자원환경지질
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• 제31권2호
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• pp.111-125
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• 1998

Dispersion, migration and enrichment of environmental toxic elements from the Samkwang Au-Ag mine area were investigated based upon major, minor and rare earth element geochemistry. The Samkwang mine area composed mainly of Precambrian granitic gneiss. The mine had been mined for gold and silver, but closed in 1996. According to the X-ray powder diffraction, mineral composition of stream sediments and soils were partly variable mineralogy, which are composed of quartz, orthoclase, plagioclase, amphibole, muscovite, biotite and chlorite, respectively. Major element variations of the host granitic gneiss, stream sediments and soils of mining and non-mining drainage, indicate that those compositions are decrese $Al_2O_3$, $Fe_2O_3$, MgO, $TiO_2$, $P_2O_5$ and LOI with increasing $SiO_2$ respectively. Average compositional ranges (ppm) of minor and/or environmental toxic elements within those samples are revealed as As=<2-4500, Cd=<1-24, Cu=6-117, Sb=1-29, Pb=17-1377 and Zn=32-938, which are extremely high concentrations of sediments from the mining drainage (As=2006, Cd=l1, Cu=71, Pb=587 and Zn=481 ppm, respectively) than concentrations of the other samples and host granitic gneiss. Major elements (average enrichment index=6.53) in all samples are mostly enriched, excepting $SiO_2$, $Na_2O$ and $K_2O$, normalized by composition of host granitic gneiss. Rare earth element (average enrichment index=2.34) are enriched with the sediments from the mining drainage. Minor and/or environmental toxic elements within all samples on the basis of host rock were strongly enriched of all elements (especially As, Br, Cu, Pb and Zn), excepting Ba, Cr, Rb and Sr. Average enrichment index of trace elements in all samples is 15.55 (sediments of mining drainage=37.33). Potentially toxic elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) of the samples revealed that average enrichment index is 46.10 (sediments of mining drainage=80.20, sediments of nonmining drainage=5.35, sediments of confluent drainage=20.22, subsurface soils of mining drainage=7.97 and subsurface soils of non-mining drainage=4.15). Sediments and soils of highly concentrated toxic elements are contained some pyrite, arsenopyrite, sphalerite, galena and goethite.

• 한국농림기상학회지
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• 제19권1호
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• pp.1-9
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• 2017

최근 논에서 밭으로 개원하는 포도농가가 증가하고 있으며, 토양 배수성이 극히 불량한 이러한 토양은 여름철의 집중호우기(장마기)때 과습 또는 침수해를 받을 우려가 매우 높다. 따라서 본 연구는 배수방법(무처리, 명거배수, 암거배수)을 달리하여 토양의 수분변화를 측정하고, 이에 따른 포도 '진옥'(Vitis spp.)과 '캠벨얼리'(V. labruscana)의 생육반응을 비교하고자 수행하였다. 집중 호우 이후 토양과습에 해당하는 -15kpa 이상의 토양수분포텐셜 유지시간은 무처리, 명거배수구, 암거배수구에서 각각 352, 348, 180시간으로 조사되었으며, 상대적으로 암거배수의 점토함량은 다른 배수처리구보다 약 8~12% 낮았다. 집중 호우 이후 작물수분스트레스지수는 암거배수가 가장 낮고 무처리가 가장 높았으며, 광합성속도는 반대의 결과를 보여 처리간 차이는 유의하였으나 품종간에는 큰 차이를 보이지 않았다. 또한 엽면적과 주간부단면적의 생장량 역시 암거배수가 무처리와 명거배수보다 효과적이었다.

• 농업과학연구
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• 제47권4호
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• pp.727-742
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• 2020

Point cloud-based 3D maps can obtain many kinds of information for maintenance work on forest road networks. This study was conducted to compare the importance of each factor to select the factors required for the mapping of 3D forest road maps. This can be used as basic data for attribute information required to maintain forest road networks. The results of this study found that out of a total of 30 indexes extracted for mapping 3D forest roads, a total of 21 indexes related to stakeholder groups were significantly different. The importance of the index required by the civil service group was significantly higher than that of the other groups overall. In the case of the academic group, the index importance for cut slope, fill slope, and drainage facility was significantly higher. On the other hand, the index importance for the forestry cooperative and forest professional engineer group was mostly distributed between the civil servants' group and the academic group. In particular, the type of drainage system showed the highest value among the detailed indexes. Overall, drainage related factors in this survey had high coefficient values. The impact of water on forest roads was the most important part in road maintenance. In addition, the soil texture had a high value in relation to slope stability. This is thought to be because the texture of the soil affects the stability of the slope.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.36-36
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• 2012

Drainage water in lowland paddy fields is quantitatively influenced recycle and/or repeated irrigation by irrigation facilities, i.e. pumps, check gates, small reservoirs and so on. In those drainage channels, nutrients accumulation and increasing organic matters are considered to be occurred, and water quality would be degraded not only environmental aspect but irrigation purpose. In general, Total Nitrogen (T-N) is interested water quality index in irrigation water, because high nitrogen concentration sometimes caused decreasing rice production by excess growth and fallen or degrading quality of taste, then, farmers would like to clear water less than 1mg/L of T-N concentration. In drainage channel, it is known that the nitrogen concentration change is influenced by physical, chemical and biological properties, i.e, stream or river bed condition, water temperature, other water quality index, and plant cover condition. In this study, discharge data (velocity and level) in a drainage channel was monitored by an Acoustic Doppler system and water quality was sampled at same time in 2011. So those data was analyzed by multi regression model to realize hydrological and environmental factors to influence with nitrogen concentration. The results showed the difference tendency between irrigation and non-irrigation period, and those influenced factors would be considered in water quality model developing in future.