중온 침출수 재순환 혐기성 소화 시스템을 이용한 음식물류 폐기물 처리

조찬휘ㆍ이병희ㆍ이용운(Chan Hui ChoㆍByong hi LeeㆍYong Woon Lee) 유기성자원학회 2016 유기물자원화 Vol.24 No.1

본 연구에서는 침출수 재순환 시스템을 적용한 중온 혐기성소화를 이용하여 음식물류 폐기물을 분해하여 메탄가스를 생산하였다. 실험은 36℃로 유지되는 항온수조 내에 생물반응조와 침출수 저장조로 구성된 2개의 동일한 시스템(System A, System B)을 사용하였고, 생물반응조 하단 30 mm위에는 스크린이 있어 고액분리를 하여 침출수 저장조로 침출수를 이송하였다. 침출수 재순환은 매일 수행하였으며, 침출수 재순환 시에는 생물반응조 하단에서 침출수 저장조로 2.5 L를 30분간 이송한 뒤 다시 침출수 저장조에서 생물반응조 상부로 2.5 L를 30분간 주입하였다. 주입된 음식물류 폐기물은 수집되기 전 한 번 세척하였으며 반응조에 주입되기 전에 36℃로 온도를 올렸다. System A에 49.1 g VS, System B에 54.0 g VS을 2주 간격으로 투입하였다. 저해인자로 측정된 항목은 NH₄⁺-N과 염도였으며, 두 가지 항목의 농도 모두 시스템에 끼친 영향은 없는 것으로 나타났다. System A는 112일간, System B는 140일 동안 운전하였는데, 각 시스템에서 인발된 슬러지는 없었다. 음식물류 폐기물의 혐기성 소화를 통한 평균 메탄 발생량은 System A의 경우 0.439 L CH4/g VS, System B의 경우 0.368 L CH4/g VS로 나타났다. In this study, mesophilic anaerobic digestion of source separated food waste was carried out by leachate recirculation system and methane gas was produced. Two systems - system A and B were fabricated and placed within water bath to maintain 36℃. Each system was comprised of an anaerobic bioreactor and a leachate tank. Leachate in bioreactor was separated through the screen located at 30 mm above the bottom and a pump was installed to transfer collected leachate to the leachate tank. Everyday, 2.5 L of the leachate was pumped from the bioreactor to the leachate tank for 30 min and transferred leachate was pumped back to the top of the bioreactor for 30min, sequentially. Source separated food waste used for this experiment was washed by water before transferring to the laboratory. Transferred food waste was warmed to 36℃ before being fed to bioreactors. System A was fed to 49.1 g VS (Volatile Solids) and System B was fed to 54.0 g VS at every two weeks, respectively. NH₄⁺-N and salinity were monitored to see the inhibition toward anaerobic bioreaction and it was found that concentrations of these materials were not high enough to affect the bioreaction. Although the food waste was fed biweekly for 112 days and 140 days at system A and B, respectively, there was no sludge withdrawal from each system. Average methane productions rates were 0.439 L CH4/g VS and 0.368 L CH4/g VS for system A and B, respectively.

Nitrate Exposure Assessment under Uncertainty

이용운,Lee, Yong-Woon,Bogardi, Istvan 한국환경영향평가학회 1995 환경영향평가 Vol.4 No.2

지하수의 질산오염 문제는 한국을 포함한 세계의 여러나라에서 보고되어 왔다. 질산염은 청색증 유발물질로서 뿐만 아니라 발암물질일 가능성도 동물실험을 통해 제기되고 있다. 대부분의 경우에 지하수 질산염의 주요 오염원은 농작물 생산량의 향상을 위해 사용하는 비료이다. 그밖에 가축의 분뇨, 산업폐기물 및 생활하수도 지역에 띠라 질산염 오염원이 될 시기는 언제인가를 결정하기 위하여 의사결정권자는 여러가지의 작물경작방법에 따라 지하수 질산오염이 어떻게 변하는지를 시계열로 예측할 필요성이 있다. 그러나 직물경작방법에 따른 지하수 질산오염을 예측하는데 필요한 토질특성, 비료의 사용량, 작물의 종류 같은 자료의 대부분은 불확실성을 내포하고 있다. 이러한 불확실성은 경제성 때문에 자료의 불충분한 조사와 인간지식의 부족으로 인해 발생한다. 본 논문에서는 불확실성을 고려하면서 작물경작방법에 따른 지하수 질산오염의 변화를 예측하는 방법을 실제적인 사례를 통해 보여준다. 그리고 자료의 불확실성을 표현하기 위해 퍼지집합이론(fuzzy set theory)은 본 논문에서 응용되었다. Nitrate contamination problems from groundwater supplies have been documented throughout many countries in the world, including Korea. Nitrate salts can induce methemoglobinemia and possibly human gastric cancer. In farmed areas. intensive agricultural activities have caused a major increase in nitrate loading to groundwater. To determine whether decision makers must take farm-management actions to control the increase of groundwater nitrate concentration and to decide the timing of such actions, it is important to predict groundwater Nitrate levels that would result over time from various farm-management practices. However, the input values such as soil, fertilizer and crop data) used to examine the effects of various farm-management practices on groundwater nitrate level are usually uncertain due to a lack of available information. In this paper. the ease of a community with a nitrate water quality problem is illustrated to examine the effects of various farm-management practices and to show bow to perform, with uncertain information. a time-series analysis on groundwater nitrate levels that would result. from each farm-management practice.

청소년의 커뮤니케이션 유형별 정치적 의사소통이 정치참여에 미치는 영향

이용운(Yong Woon Lee),하승태(Sungtae Ha) 부산울산경남언론학회 2015 지역과 커뮤니케이션 Vol.19 No.1

본 연구는 미래 민주주의 발전 과정에서 청소년의 정치참여가 중요하다는 인식하에 청소년들의 정치참여에 미치는 다양한 커뮤니케이션 유형(대인커뮤니케이션, 매스미디어, 뉴미디어)의 영향을 분석하였다. 주요 분석 결과를 보면 청소년들의 친구, 부모, 형제, 선생님 등과의 일상적 대화는 정치참여에 별다른 영향을 미치지 않았지만 친구 혹은 형제와의 정치적 이슈와 관련된 대화는 청소년의 정치참여에 긍정적인 영향을 미친 것으로 나타났다. 부모의 경우 특정 정당에 대한 지지를 보일 때 청소년들의 정치참여는 오히려 감소하는 것으로 나타났다. 전통적 미디어 이용에 대한 분석에서는 잡지를 제외한 모든 미디어의 이용이 청소년들의 정치참여에 긍정적 영향을 미치는 것으로 나타났으며, 뉴미디어 이용에 대한 분석에서는 DMB 시청만이 정치참여에 유의미한 영향을 미치는 것으로 분석되었다. 결국 청소년들의 커뮤니케이션 유형 중 또래집단과의 정치대화와, 전통미디어가 정치참여에 가장 큰 영향을 미치는 것으로 나타났다. 연구결과에 대한 정치사회적 함의가 결론부분에서 논의되었다. This study has discussed about the influence of various types of communication (interpersonal communication, mass media, and new media) on adolescents. According to the major results of analysis, normal communication of adolescents with friends, parents, brothers/sisters, and teachers has not much influenced on participation in politics. However, conversation related to political issues with friends or brothers/sisters was turned out to significantly influence on adolescents’ participation in politics. On the other hand, it was turned out that political participation of adolescents was decreased as parents supported a particular party. However, awareness of adolescents on parents’ approval rating on a particular party was confirmed to increase the use of traditional political media news leading them to eventually participate in politics. Concerning the use of traditional media, all the medias except magazines positively influenced on political participation. According to analysis on the use of new media, it was shown that only watching DMB significantly influenced on the political participation. At last, conversation of political issues with peer groups and traditional media were the biggest factors among the types of communication of adolescents influencing on the political participation. Analysis of each of the major types of communication that can influence on political participation of adolescents is expected to provide important empirical resource on a course of development in democracy in the future.

BASINS/HSPF와 연계한 유활별 비점유달부하량 산정방법 개발

이용운(Yong Woon Lee),송광덕(Kwang Duck Song),이재춘(Jae Choon Lee),윤광식(Kwang Sik Yoon),류덕희(Doug Hee Rhew),이수웅(Su Woong Lee),이신후(Shin Hoo Lee) 大韓環境工學會 2010 대한환경공학회지 Vol.32 No.2

퍼지 Simulation 방법에 의한 주암호의 수질모델링

이용운(Yong Woon Lee),황윤애(Yun Ae Hwang),이성우(Sung Woo Lee),정선용(Seon Yong Chung),최정욱(Jung Wook Choi) 大韓環境工學會 2000 대한환경공학회지 Vol.22 No.3

도 · 송수로 노선의 평가를 위한 퍼지 의사결정 지원 시스템

이용운(Yong Woon Lee),김주환(Ju Hwan Kim),최두용(Doo Yong Choi) 大韓環境工學會 1997 대한환경공학회지 Vol.19 No.6

TDX-10 가입자 정합회로의 Digital, Analog 성능 측정

이용운(Yong-Woon Lee),정준건(Jun-Gun Chung),장승혁(Seung-Hyeock Chang),지용(Yong Jee),남홍순(Hong-Soon Nam),김진태(Jin-Tae Kim),이현(Hun Lee) 한국통신학회 1994 한국통신학회 학술대회논문집 Vol.1994 No.7

임금만족 측정도구의 타당성 평가

이용운(Yong-Woon Lee) 한국고용노사관계학회 2000 産業關係硏究 Vol.10 No.1

The purpose of this research is to empirically examine the validity of Pay Satisfaction Questionnaire developed in Korea. The dimensionality of the KPSQ is consistent and the cronbach alpha estimates were all high in all sets of items that was confirmed internally consistent in KPSQ. This measurement model exhibited good fit, assessed by overall fit measures criteria and lambda score with confirmatory factor analysis. And this research model was confirmed generalizable in a cross-validation study applied the other heterogeneous companies' employee groups and was confirmed convergent and discriminant validity by multitrait-multimethod matrix analysis result. In the nomological network test, correlation between this measurement and face scales, organization attachment, and turnover intention indicated a result similar to previous studies that assisted the construct validity. Therefore, KPSQ was inferred to take a validity and generalizability from this collected data. Implication of this work for future theoretical and empirical development are suggested.

퍼지 의사결정법에 의한 주암호 수질관리 전략 평가

이용운(Yong Woon Lee),황윤애(Yun Ae Hwang),이성우(Sung Woo Lee),이병희(Byong Hi Lee),최정욱(Jung Wook Choi) 大韓環境工學會 2000 대한환경공학회지 Vol.22 No.4

소형 우드 펠릿 보일러의 연소 효율 향상을 위한 연구

이용운(Yong-Woon Lee),예인수(In-Soo Ye),이명일(Ming-Ri Li),홍재현(Jae-Hyeon Hong),오정근(Jeong-Geun Oh),이웅진(Ung-Jin Lee),류창국(Chang-Kook Ryu) 한국연소학회 2010 KOSCOSYMPOSIUM논문집 Vol.- No.40

Wood pellet is a densified fuel with homogeneous physical properties suitable for use in various scales of domestic and industrial furnaces. A wood pellet stove is a small-scale furnace for domestic heat production, which can replace the conventional oil or gas boilers. Since the fuel properties of wood pellet is very different from oil or gas, the design of a wood pellet stove requires profound understanding on the solid fuel combustion as well as gas flow mixing/reactions. Due to the size limit of the furnace height (~1m) for domestic installation, poor design of furnace, air supply and heat exchanger may lead to excessive emission of CO or low energy efficiencies. This study evaluated the design of an existing wood pellet stove with 30,000 ㎉/hr capacity using experimental and computational techniques in order to optimize the furnace design. The results show that it is critical to minimize the unused furnace volume and to enhance the gaseous mixing for reduced CO emission.