• 자원리싸이클링
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• 제7권4호
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• pp.55-63
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• 1998

냉연공장의 산회수 설비로부터 제조되는 소프트 페라이트용 산화철의 품질편차를 감소시키기 위한 연구로서, 품질편차 원인분석, 산회수 조업조건 및 산화철 성분분석, 그리고 산화철의 품질변화를 조사하고 이로부터 도출된 산화철 품질편차 최소화를 위한 적정 조업 pattern을 확립하였다. 산화철의 품질편차를 감소시키기 위해서는 산화철의 원료가 되는 폐산의 발생, 즉 산세처리 대상재인 강종의 구분과 발생 폐산의 분리저장 및 분리운전이 필요하였다. 폐산의 분리, 운전조업 및 생성 산화철의 분리, 저장으로 $SiO_2$함량 약 80ppm, 편차 $\pm$ 10 ppm 이하의 산화철을 제조할 수 있었다. 추가필터 설치의 운영에 따라 산화철의 품질편차 감소뿐만 아니라 고순도 산화철의 생산도 가능할 것으로 예상되었다.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2001년도 추계학술대회 논문집
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• pp.203-206
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• 2001

Finding the optimal solution in the river water quality management system is very hard with the non-linearity of the water quality model. Many suggested methods for that using the linear programming, non-linear programming and dynamic programming, are failed to give an optimal solution of sufficient accuracy and satisfaction. We studied a method to find a solution optimizing the river water quality management in the aspect of the efficiency and the cost of the waste water treatment facilities satisfying the water Quality goals. In the suggested method, we use the QUAL2E water quality model and the genetic algorithm. A brief result of the project to optimize the water quality management in the Youngsan river is presented.

• 상하수도학회지
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• 제12권3호
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• pp.41-47
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• 1998

Doam Lake is located around the pasture area and Yongpyung Resort. Because of the waste load of domestic animals, nutrient concentration of the stream is high. In this study, waste load of Doam Lake watershed is calculated, and QUAL2E model is applied to the upper part of the Songcheon to calculate the input boundary concentration of Doam Lake. And WASP5 model is applied for the water quality modeling of Doam lake. The results indicate that advanced treatment of domestic animal wastes is necessary for the lake water quality management.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 봄 학술발표회 논문집
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• pp.197-202
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• 1994

This study is designed for analyzing the physical properties of grading, shape, specific gravity and etcetera of mine-waste as the aggregate of concrete when mine waste is crushed by jaw crusher, and is aimed presenting the using the possibility, content and reference data for the quality control of practical use on the concrete using the mine-waste aggregate.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2001년도 학술발표회 발표논문집
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• pp.111-114
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• 2001

This study is a fundamental research for recycling waste vinyl in asphalt concrete mixture for roadway pavement. The mixing method and proper content of waste polyethylene(PE) film were determined through preliminary mix design. This study used 2-type aggregate gradations and two-type waste PE films. The mixtures were applied for a test pavement on a rural road. Quality evaluation of the asphalt concrete confirmed that waste vinyl asphalt concrete was applicable to road pavement.

• 한국안전학회지
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• 제11권3호
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• pp.160-167
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• 1996

The construction waste concrete produce from the demolished concrete structures. These waste concrete materials are useful and valuable for fill and subgrade and are considered to use as the subgrade material of the road. To use the subgrade of the road with the waste concrete, the several experiments involved with compaction test and laboratory C. B. R. etc. are performed. These experiments are compared with criteria of the road construction manual. It is shown that the quality of the construction waste concrete satisfies that of the subgrade mentioned in the road construction manual.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.631-636
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• 2002

This study shows basic data for using as the structural lightweight aggregate. This will be the procedural method of recycling environmental close waste PET bottle lightweight aggregate(PBLA) that is rapidly increased the amount of production of waste PET bottle recently, the quality of developed PBLA and the fundamental properties by analyzing of mortar containing with PBLA. After experiment, the result shows the PBLA quality that have oven dry specific gravity of 1.39, unit volume weight of 844 kg/m$^3$ and absorption rate of 0% is satisfied with qualify regulation of lightweight aggregate. The flowability of mortar containing PBLA is increased maximum 16% with increasing mixing ratio of PBLA, however the compressive strength of mortar is decreased maximum 35% with increasing mixing ratio of PBLA.

• 환경위생공학
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• 제16권2호
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• pp.56-62
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• 2001

This study is carried out to investigate the water quality changes in Busan Metropolitan streams, The results are as follows. The level of organic contaminants($BOD_{5}$ and $COD_{Mn}$) is found to be low and does not show seasonal variation in domestic waste water streams. But, the level of organic contaminants in industrial waste water streams is relatively high and seems to be seasonally variable, which is affected by other factors. The nutrient materials, such as nitrogen(as T-N, about 20mg/L) and phosphorus(as T-P about 2.0mg/L), are abundant than Nak Dong River and the general trends of contaminants level are similar to those of organic contaminants. The chronic water qualities, including organic, nutrient contaminants levels, show that the loading rates in 1998 are smaller than the past(1983, 1992). And this trend is more evident in industrial waste water streams than domestic waste water streams.

• 대한지역사회영양학회지
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• 제5권2호
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• pp.316-323
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• 2000

This study was carried out to evaluate nutritional quality of the dosirak severed by 3 Dosirak manufacturing establishment in Kangnung. The subjects of this study came from 3 different male high schools in Kangnung. The portion amounts of Dosirak were weighed and the food intake was measured by substracting the leftover from the averaged portion amount. The leftover was measured by a modified aggregate selection plate waste measurement technique. The nutrient intakes were analyzed by a computer aided nutritional analysis program for professionals(CAN pro). The menu of the dosirak was too simple. The total amount of Dosirak was 714g and the percent of plate waste was 714g and the percent of plate waste was 7.2%. The male high school students were taking adequate energy, but the nutrients which did not meet 75% of the 1/3RDA(Recommended Dietary Allowances) were Ca, Fe, and vitamin B$_2$.

• 유기물자원화
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• 제13권1호
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• pp.61-70
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• 2005

우리나라 음식물 쓰레기를 자원화하여 사료나 퇴비로 활용되는 과정에서 일어나는 고농도의 염분 문제를 해결하고 자원화 공정에서 배출되는 침출수의 수질 개선을 위하여 음식물 쓰레기에 소량의 물을 첨가하여 희석/탈수방법에 의한 로터리식 저염화 공정설비를 설계 제작하여 음식물 쓰레기에 함유된 염분 저감 실험을 수행하였다. 개발된 로터리식 저염화 공정설비는 시간당 0.5톤의 음식물 쓰레기를 연속적으로 투입할 수 있는 파이롯트 설비이며, 설비 가동시 첨가되는 물의 양은 음식물 쓰레기의 함수율에 따라 산출되는데 음식물 쓰레기 1kg당 약 0.8리터의 수돗물이 일정한 유속으로 로터리형 저염화 반응조에 분사 투입되면서 희석/교반/탈수공정에 의하여 저염화가 진행되는 구조이다. 설비의 성능 평가를 위하여 대학의 구내식당에서 배출되는 음식물 잔반을 수거한 그대로 설비에 투입하여 시험가동을 거친 후 실증 실험을 수행하였는데 염소이온의 침전 적정법, 전극에 의한 salinity측정법으로 염분의 저감도를 평가한 결과 음식물 쓰레기를 1차 탈수한 후 희석/교반/탈수에 의한 운영방법으로 항상 50%이상의 염분 저감효율을 얻을 수 있었다. 설비가동시 배출되는 침출수는 첨가된 물의 양을 포함하여 음식물 쓰레기 1kg당 약 1.1리터가 배출되는데 유기고형물질의 양이 매우 많아서 망에 의한 중력여과와 원심분리에 의한 고액분리에 의하여 유기성 고형 물질을 대부분 회수하여 자원화용으로 반출될 제품에 재투입하여 자원화용으로 반출될 제품의 품질 저하를 감소시킬 수 있었으며, 최종 침전조 상등수의 TS가 최저 $200mg/{\ell}$까지 수질 개선 효과를 얻을 수 있었다.