불산 가스 누출 시 피해 우려지역의 환경정의 특성 분석

Yong Un Ban,Sang Sup Lee,Gyeong Ho Jin,Jong In Baek,Na Eun Hong,Sang Wook Gang,Tae Ho Kim 위기관리 이론과 실천 2017 Crisisonomy Vol.13 No.2

본 연구의 목적은 불산 가스가 누출되는 사고가 발생했을 경우 피해가 우려되는 지역의 환경정의 특성을 분석하는 것이다. 분석방법으로는 대기질에 미치는 영향범위 및 정도를 예측하기 위하여 대기확산모델인 AERMOD와 사회ㆍ경제적 특성을 살펴보기 위하여 ArcGIS를 사용하였다. 피해 우려지역과 피해 비 우려지역의 사회ㆍ경제적 특성을 비교한 결과는 다음과 같다. 1) 피해 우려지역의 경우, 평균 공시지가 562,127원, 평균 14세 이하 인구 비율 19.93%, 평균 65세 이상 인구 비율 6.3%이다. 반면, 피해 비 우려지역의 경우 평균 공시지가 184,293원, 평균 14세 이하 인구 비율 17.85%, 평균 65세 이상 인구 비율 8.63%이다. 따라서 피해 우려지역의 평균 공시지가가 비 피해 우려지역보다 약 3배 높았고, 14세 이하 인구 비율은 약 2% 높게 나왔고, 65세 이상 인구 비율은 약 2% 낮게 나왔다. 2) 피해우려지역 내에서 불산 가스의 농도가 0.1 ppm에서 0 ppm으로 갈수록 평균 공시지가는 낮아졌지만, 14세 이하 인구 비율, 65세 이상 인구비율, 평균 어린이 이용시설 개수는 증가하였다. This study intends to analyze environmental justice characteristics of the areas expected to be exposed (AEE) to hazardous Hydrofluoric (HF) acid gas in case of leakage accident. The findings from this study include: (1) in comparison to the areas not expected to be exposed (ANEE), the average value of public lands was three times higher, the proportion of children aged 14 years old or less appeared 2 percent higher, and the proportion of elderly aged 65 years old or more appeared 2 percent lower in the AEE, (2) for an increase of hazardous Hydrofluoric (HF) acid gas concentration from 0.1ppm to 0ppm in the AEE to the damage, the average value of public lands decreased while the proportion of children aged 14 years old or less, the proportion of elderly aged 65 years old or more and the average number of children s facilities increased.

열경화성 연속섬유 복합재를 이용해 외측 보강된 3D 프린팅 열가소성 복합재 구조물의 굽힘 특성 향상에 대한 연구

백운경 ( Un-gyeong Baek ),남기법 ( Gibeop Nam ),노재승 ( Jae-seung Roh ),박성은 ( Sung-eun Park ),노정우 ( Jeong-u Roh ) 한국복합재료학회 2021 Composites research Vol.34 No.2

3D 프린팅 기술은 금형이 없이 다양한 형태의 제품을 만들기 쉬운 장점이 있지만, 기존 보편화된 성형법에 비해 기계적 물성이 낮고, 소재 및 제작 조건 등에 따라 기계적 물성이 크게 달라지는 문제가 있다. 한편, 높은 물성을 구현하기 위해서는 제조비용이 높아지는 문제가 있어, 이에 대한 연구 필요성이 증가하고 있다. 본 연구에서는 단섬유 탄소섬유 보강 나일론 필라멘트를 이용하여 3D 프린팅 열가소성 구조물을 제작하였다. 또한 인발 성형된 연속섬유 형태의 탄소섬유 혹은 유리섬유 강화 열경화성 복합재를 이용해 외측면을 보강하여 기계적 물성 향상 방법을 제시하였다. 보강재의 보강 위치와 섬유의 종류에 따른 굽힘물성 향상을 확인하였다. 3D printing technology has the advantage of easy to make various shapes of products without a mold. However, it has a problem such as mechanical properties vary greatly depending on materials and manufacturing conditions. Thus, the need for research of 3D printing technology on ways to reduce manufacturing cost compared to physical properties is increasing. In this study, a 3D printing thermoplastic structure was fabricated using short fiber carbon fiber reinforced nylon filaments. And a method of improving mechanical properties was proposed by reinforcing the outer surface using pultruded continuous fiber-type carbon fiber or glass fiber-reinforced thermosetting composite material. It was confirmed that the bending properties were improved according to the reinforcing position of the stiffener and the type of fiber in the stiffener.

Cell membrane permeabilization of kelp (Saccharina japonica) by pulsed electric fields pretreatment and its impact on dehydration and extraction process

Hyun Su Choi,Han Baek Lee,Gyeong Seo Park,Se Ho Jeong,Dong Un Lee 한국산업식품공학회 2023 학술대회 및 심포지엄 Vol.2023 No.04

공기에 의한 탄소섬유 스프레딩 공정 변수에 따른 프로세스 성능 및 기계적 물성 평가

노정우 ( Jeong-u Roh ),백운경 ( Un-gyeong Baek ),노재승 ( Jae-seung Roh ),남기법 ( Gibeop Nam ) 한국복합재료학회 2020 Composites research Vol.33 No.6

탄소섬유 스프레드 토우를 제조하는 과정에서 섬유 손상이 발생하며, 이는 스프레딩 과정에서 장비와 섬유 사이 혹은 섬유 간의 마찰로 발생한다. 이로 인해, 재료 및 장비조건에 따라 프로세스 성능에 차이가 발생하고, 제품 물성이 하락한다. 섬유 손상을 최소화하는 것은 스프레드 토우를 제조하는 공정에서 반드시 고려되어야 한다. 본 연구에서는 공기를 이용한 탄소섬유 스프레딩 공정에서 탄소섬유의 필라멘트 수와 사이징 함량, 탄소섬유토우 스프레딩 장비의 공정 변수(초기섬유장력, 열풍온도, 진공압력)를 달리하여 스프레드 토우의 공정성능 변화를 관찰하였다. 탄소섬유 품종에 따른 조건 별 최적조건에서 제조된 샘플을 이용해 인장강도를 평가하여, 탄소섬유의 손상에 따른 기계적 물성 감소를 확인하였다. The carbon fiber has been damaged via tow spreading process for carbon fiber spread tow. The fiber damage is caused by friction between equipment and fibers or between fibers and fibers in the process of spreading. As a result, mechanical properties are decreased due to differences in process via material and equipment condition. Therefore, minimizing fiber damage have to be considered in the process. In this study, the change in carbon fiber pneumatic spreading process was observed by according to the filament count, sizing content of carbon fiber and process variables in spreading equipment (fiber tension at the beginning, air temperature in spreading zone, vacuum pressure in spreading zone). Tensile strength was evaluated using samples prepared under optimal conditions for each of the carbon fiber varieties, and mechanical properties were reduced due to damage on the carbon fiber.

불산 가스 누출 시 피해 예상지역 간 사회 · 경제적 차이 비교를 통한 환경정의특성 분석

김태호(Kim,Tae-Ho),엄상필(Um,Sang-Pi),백종인(Baek,Jong-In),진경호(Jin,Gyeong-Ho),이상섭(Lee,Sang-Seop),반영운(Ban,Yong-Un) 한국환경정책학회 2015 한국환경정책학회 학술대회논문집 Vol.2015 No.10

Manufacturing strategy for a powder-based Fe-6.5%Si steel by powder rolling

Ki Hyuk Kwon,Yong Seok Choi,Do Hee Kim,Un-Gyeong Baek,Min-Ho Kwon,Eon Sik Lee 한국자기학회 2022 한국자기학회 학술연구발표회 논문개요집 Vol.31 No.2

탄소계 소재를 이용한 극저주파 영역에서의 자기 차폐효과 연구

오성문,강동수,이상민,백운경,노재승,Oh, Seong Moon,Kang, Dong Su,Lee, Sang Min,Baek, Un Gyeong,Roh, Jae Seung 한국전력공사 2015 KEPCO Journal on electric power and energy Vol.1 No.1

To examine the magnetic shielding effect for carbon-based materials at extremely low frequencies (60 Hz), two types of carbon black (Super-P and Denka Black) and a natural graphite (HC-198) were mixed into organic binder at 10 wt.% to produce a coating solution, and a powder coating with varying thickness was applied on an aluminum disk measuring 88 mm in radius. A device was developed to measure the sheielding effect at extremely low frequencies. A closed circuit was achieved by connecting a transformer and a resistor. The applied voltage was fixed at 65 V, and the magnetic field was measured to being the range of 4.95~5.10 mG. Depending on the thickness of the coating layer, the magnetic field showed a decreasing trend. The maximum decrease in the magnetic field of 38.3% was measured when natural graphite was coated with specimens averaging $455{\mu}m$. This study confirmed that carbon-based materials enable magnetic shielding at extremely low frequencies, and that the magnetic shielding effect can be enhanced by varying the coating thickness.

만경강 유역의 토양과 수도체중 Cd 및 Zn 함량의 변화

백승화,김성조,문광현,김운성,윤기운,강경원 한국환경농학회 1994 한국환경농학회지 Vol.13 No.2

수질오염에 따른 Cd 및 Zn의 함량변화 차이를 구명하기 위하여 도시하수 및 공단배출수의 영향을 받는 만경강 유역의 논토양을 중심으로 1982년도와 1990년도에 표토와 심토로 구분하여 채취한 토양시료를 그리고 1990년도의 토양시료 채취지역에서 재배된 수도체 시료중 Cd 및 Zn 함량을 분석하여 그 변화를 분석하였다. 만경강 유역의 토양 중 이들 중금속 분포는 Cd이 0.38-1.17, Zn이 33.8-464.6㎎ ㎏^-이었다. 년도별 함량변화에서 Cd 함량은 1990년도 토양이 1982년도 보다 낮았고, Zn 함량은 반대로 1982년도 토양이 1990년도 토양 보다 낮았다. Cd의 경우 도시하수 및 공장폐수 배출지로부터 거리별 변화가 분명하지 않았으나, 토양의 유기물함량, 유효규산, CEC, 치환성 Ca^(++) 함량과 유의성 있는 상관관계를 나타내었다. 또한 이 지역의 토양 중 Cd 함량은 1982년도 심토 중 Cd 함량은 토양 중 Zn, Cu 및 Pb 함량과 유의한 상관관계를 나타내었다. Zn의 경우는 거리가 멀 수록 그 함량이 낮아지는 경항이 있었으며, 1982년도 토양 중에서 유기물 함량과 치환성 Ca^(++) 함량과, 그리고 년도에 관계없이 토양 중 Cu와 Pb 함량과 유의성있는 상관관계를 나타내었다. 한편 이 지역의 수도체 부위별 Cd 함량은 현미중 농도에 비해 엽신 중의 농도가 최고 7배 이상이 되었고, Zn의 경우는 엽신과 화서축 중에서 흡수축적량이 높았으며, 토양 중 Zn, Cu, Pb의 존재는 수도체의 화서축 중의 Cd 함량과 또 수도체의 모든 부위별 Zn 함량과 유의성 있는 상관관계를 나타내었다. 만경강유역의 현미 중 Cd의 함량은 0.10-0.90㎎ ㎏^(-1)이었고, Zn의 함량은 4.2-95.9㎎ ㎏^(-1) 범위였다. To investigate differences in Cd and Zn contents of paddy soils and rice plants polluted by the municipal and industrial waste water in the Mangyeong River Area, soil and plant samples were collected at several distances from the main inlet and at different depths of the soil. Soil samples were extracted with 4M-HNO₃ and plant samples were digested with a mixture of HNO₃and HClO₄for analyzing heavy metals by atomic absorption spectrophotometry. The contents of Cd and Zn in soils ranged from 0.38 to 1.17 and from 33.8 to 464.6㎎ ㎏^(-1), respectively. The average Cd level in 1990 was less than that in 1982, but the Zn level in 1990 was higher than that in 1982 in general. No variation in Cd contents was observed in soils at the different distances from the source of waste water, but Zn contents in soils were lower with the increasing distances from the source of waste water. A significant correlation was observed among Cd content, OM, available silicate, CEC and Ca^(++). Similar results existed among Zn content of 1982, OM and Ca^(++). The Cd content in subsurface soils of 1992 was significantly correlated with Zn, Cu, and Pb in soils, and the Zn content in soils was significantly correlated with the Cu and Pb in soils, regardless of years. The Cd content in leaf blades of rice was more than seven times higher than that in brown rice. The Zn content in rice was higher than that in leaf blades and in panicle axis. The Cd content in panicle axis and the Zn content in all parts of rice were correlated with Zn, Cu and Pb contents in soils. The Cd and Zn contents in brown rice ranged from 0.10 to 0.90㎎ ㎏^(-1) and from 4.2 to 95.9㎎ ㎏^(-1) in the Mangyeong River Area, respectively.

결명자 첨가식이가 흰쥐의 체내 카드뮴 축적에 미치는 영향

김성조,백승화,허종욱,김운성,이주돈,강경원,박성혜,한종현,정성윤,이승현 동아시아식생활학회 2002 東아시아食生活學會誌 Vol.12 No.6

The purpose of this study is to investigate the effect of raw Cassia tora L. powder added-diets on reducing cadmium accumulation in rats. The experimental animals were Sprague-Dawley family(♂ , 4 weeks) which was classified into normal group CN, compared group CS, Cd-added group C1 and groups C2, C3. C4 in which 0.5, 1.0 and 1.5% of the Cassia tora L. powder are added, respectively. The growth rate and food efficiency ratio, and the amounts of accumulated cadmium in rats for 8 weeks were measured and analyzed. The results are as follows; 1. The rates of weight gain decreased in the order of C3>C2>C4>Cn>Cs>C1 groups, and C1 group to which only cadmium water had been fed was the lowest among them. The correlation between groups C1 and C3 was significantly different at the 1% level. 2. Food efficiency ratio(FER) decreased in the order of C3>C2>Cs>Cn>C4>C1, and the FERs of C3, C2, CS, CN and C4 are greater than that of C1 by 22.87, 19.89, 18.54, 14.20 and 13.17%, respectively. 3. As fix the Cassia tora L. powder-added groups, the amounts of cadmium accumulated in organs and tissues that is, the brain, heart, spleen, liver, lungs, testicles, kidney, femoral muscle and leg bones were 0.45±0.04 to 0.83±.04, 1.68±0.02 to 2.16±0.02, 3.26±0.05 to 4.62±0.27, 37.82±0.09 to 47.71±0.73, 1.07±0.10 to 1.66±0.04, 1.04±0.06 to 1.24±0.08, 36.79±0.20 to 39.61±0.53, 0.87±0.02 to 1.00±0.02 and 0.65±0.17 to 1.27±0.06 ㎍/g respectively. 4. The accumulated Cd content for C4 was the lowest among Cassia tora L. powder-added groups. When the results for C4 are compared with those for C1, it is observed that each cadmium content accumulated in the brain, heart, spleen, liver, lungs, testicles, kidney, femoral muscle and leg bones is dropped by 49.03, 22.56, 36.02, 35.75, 41.75, 36.20, 37.00, 22.77 and 56.67%, respectively. On the other hand, the accumulated Cd content increased in the order of brain <leg bones <femoral muscle <testicles <lungs <heart <spleen <kidney <liver. 5. The average Cd accumulation rate in organs and tissues relative to the total Cd intake was 7.14% for C1, while they are 4.91, 4.81 and 4.509a for Cassia tora L. powder-added groups C2, C3 and C4, respectively. 6. The Cd content accumulated in the hair for C1 was the highest, and those for Cassia tora L. powder-added groups gradually increased until 6 weeks and decreased after that. 7. The Cd content accumulated in the feces for C4 was the highest, and those for the groups other than C3 and C4 gradually decreased until 6 weeks and increased after that.