• 한국환경과학회지
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• 제16권3호
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• pp.299-310
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• 2007

It will be necessary to make proper management plans to preserve the air quality in good level for the public. In order to make these plans, source information and detail emission inventories of the city and near industrial areas should be given. However, lack of the source measurements data makes us more difficult to complete the source inventory. VOC source Inventory could be utilized for the feasibility study to estimate the contribution of VOC sources presenting to the receptor such as residential area. It may give policy maker an idea how to control the air quality, and improve their social environment in the area. This study shows data that measured VOCs concentrations from the local industrial areas in Jeonju during from May 2005 to January 2006. The samples were collected from the near sources in 7 major factories in the industrial park as well as 5 general sources in near city Jeonju area to elucidate the abundances of speciated VOCs and their spacial and temporal distributions depending on source bases. Industrial sources are as follows; chemical, food, paper, wood, metal, non-metal (glass), and painting (coating) industries. The 5 general sources are sampled from tunnel, gasoline gas station, dry cleaning shop, printing (copy) shop, and road pavement working place in urban area. To understand the near source effect at receptor, samples from the 2 receptor sites (one is at center of the industrial complex and the other site is at distance residential area downwind from the center) were collected and analyzed for the comparison to source concentration. The mass contributions of the speciated VOC to total mass of VOCs measured from the different sources and ambient (2 receptors) were presented and discussed.

• 한국대기환경학회지
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• 제11권3호
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• pp.279-290
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• 1995

Recently in Korea, due to the significant drop of lead and bromine levels as a marker of autoemission source in the urban areas, the conventional application of receptor methods has many difficulties to properly apportion mass contribution of some sources. It is then needed to urgently develop alternative source profiles and identify new emission markers. Thus, the study has extensively examined the results obtained from using PAHs and elemental data for receptor modeling and has provided an opportunity to identify alternative source compositions and to determine a proper number of the ambient emission sources in Seoul area. The purpose of the study is to identify the sources of PM-10 and to estimate their mass contributions in Seoul area. Thus, a receptor model, target transformation factor analysis(TTFA) has been massively applied. The TTFA offers the possibility of determining the number of sources and their mass contributions. The input data used in this study are composed of two separate sets: fine (d$_{p}$ < 2.5.mu.m) and coarse (2.5.mu.m < d$_{p}$ < 10.mu.m) mode aerosol samples. Each sample was simultaneously collected by a PM-10 dichotomous sampler during the daytime(8 AM to 8 PM) and the nighttime(8 PM to 8 AM) from February to October 1993 on the Sungdong-Gu, Seoul. All the samples were analyzed to determine the levels of 10 inorganic elements by an XRF system as well as 14 PAHs by a HPLC. However, only 8 inorganic elements and 7 PAHs were used for the various statistical analysis.sis.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.125-129
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• 2003

The identification of location and strength distribution of extended noise sources is important in the practical noise control engineering, especially in the viewpoint of dealing with the inherent nature of noise problem in question. For noise source ranking inside an automotive vehicle, the window method has been mainly used due to its simplicity. However, time and cost drawbacks in the measurement and inaccuracy due to low-frequency tunneling and lack of phase information have been a serious problem in using this method. In this study, the inverse FRF method was employed to carry out the noise source ranking inside an automotive vehicle and it was also used to predict the interior sound pressure with the change of sound insulation materials. As a result, it was found that the source contribution of vehicle panels could be successfully identified in comparison with the window method. The sound pressure at driver's ear position was predicted based on the obtained data and was compared with the measured data. The agreement in spectral trends was acceptable and their difference in level was within 3㏈ above 500㎐.

• 한국음향학회지
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• 제37권5호
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• pp.300-308
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• 2018

자동차 실내음에 대한 다양한 외부 공력 소음원들의 기여도 분석은 저소음 자동차를 개발하기 위해 단순히 외부 공력 소음원들을 파악하는 것보다 개발 효율성 측면에서 더 중요하다. 파악된 외부 공력 소음원들의 실내음 기여도를 분석하기 위하여 촐레스키 분리(Cholesky Decomposition, CD) 방법이라는 새로운 기법을 활용하여 전체 실내 소음 스펙트럼을 다수의 스펙트럼으로 분리하였다. 이를 통해 분리된 각각의 스펙트럼은 실내 소음에 대한 특정한 개별 소음원들의 기여도로 분석될 수 있다. 이 방법을 검증하기 위해 세가지 실험들이 수행되었다. 더 나아가 CD에 기초한 실내음 기여도 분석 방법은 실차 무향 풍동에서 마이크로폰 어레이를 통한 외부 소음원 가시화 결과와 결합하여 바람소리 개발 효율성을 향상시키는 데 활용이 가능한 지를 2개의 스피커 소음원 실험을 통해 검증하였다.

• Journal of Nutrition and Health
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• 제33권8호
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• pp.882-889
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• 2000

This study was conducted to examine contribution of specific foods to absolute intake and between-person variation in nutrients consumed by 2037 adults living in Korean rural area using one day 24-hour recall method. To measure contribution of food to absolute nutrient intake, all foods consumed were ranked by percentages calculated as the sum of the nutrient intake contributed by a given food divided by the total nutrient intake from al categories. To assess between-person variability in nutrient intake, stepwise multiple regression analysis was used with total nutrient intake from al foods as the dependent variable and the nutrient amount from each of all foods as independent variables. The kind and the number of foods necessary to account for the variation in nutrient intake among persons varied significantly depending on the nutrient. The nutrients contributing more than 80% of total intake with a few number of food items were ${\beta}$-carotene(ll), vitamin C(15) and vitamin A(16). Foods sometimes overlooked as important sources were found in some instances to be quantitatively important to population intake. Even though rice and Korean cabbage kimchi do not contain much nutrients in quantity, they made a major contribution to most nutrient intake of subjects because of large serving size and high frequency of intake. The food items and contributing order for between person variance was different from those of absolute intake. A large fraction of the variability of nutrient intake in this population was explained by a small number of foods. Fewer foods were required to explain a given proportion of the between-person variance in intake than to account for the same proportion of the popylation\`s total intake. These data may be useful in the development of dietary assessment instrument and in nutrition education. (Korean J Nutrition 33(8) : 882-889, 2000)

• Korean Chemical Engineering Research
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• 제54권2호
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• pp.187-199
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• 2016

구미공단 대규모합성섬유제조업체들의 총괄 점오염원 및 개별 점오염원에 의한 각각의 트리메틸아민 관련 기여도 평가예측을 위하여 CALPUFF 모델링을 수행하였다. 또한 개별 점오염원의 총괄 점오염원에 대한 트리메틸 관련 상대적 기여도를 산출하였다. T사 배출설비 개선 후 총괄 점오염원의 트리메틸아민 배출에 의한 본 연구 CALPUFF 모델링 결과로서 2011년 겨울(1월), 봄(4월)에는 주로 구미 3공단에서, 여름(7월), 가을(10월)에는 주로 구미 1공단에서 트리메틸아민 농도의 최대값이 도출되었다. 한편 T사 배출설비 개선 후에는 구미 1공단의 경우에 트리메틸아민 예측 최대값 범위가 매우 개선되었음이 확인되었다. 반면에 구미3공단의 경우는 T사 배출설비 개선 후에 오히려 트리메틸아민 예측 최대값의 상한치가 더욱 커졌으나 그 상한치를 제외하였을 때는 T사 배출설비 개선 전의 트리메틸아민 측정치의 상한치와 비슷하였다. 이와 같이 T사 배출설비 개선이 공단별 트리메틸아민 농도에 미치는 영향이 구미 1공단에서는 컸으나 구미 3공단에서는 미미한 수준이었다. 한편 본 연구 CALPUFF 모델링 결과로서 트리메틸아민 농도 예측치는 트리메틸아민 농도의 측정치 범주와 거의 일치하므로 본 연구의 총괄 점오염원에 의한 트리메틸아민 기여도 평가에 대한 유효성을 보여주었다.

• 한국통신학회논문지
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• 제25권10A호
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• pp.1566-1575
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• 2000

이 논문은 일반화된 감마 신호원에 최소 평균제곱오차 왜곡을 갖도록 설계된 양자기가 다른 신호원에 사용될때 발생하는 양자기 불일치에 대한 연구로서, 양자기의 여러 불일치 가운데, 설계 신호원과 사용 신호원의 분산이 불일치된, 분산 불일치 문제를 다루었다. 주 내용은 베넷 적분식을 기반으로 하여 유도한 양자기 왜곡의 두 근사수식으로, 첫째 근사식은 양자기의 맨 바깥 경계값의 함수로 표시된 제1차 왜곡 근사식이며, 둘째 근사식은 이 맨바깥 경계값의 근사식을 사용한 제2차 왜곡 근사식이다. 일반화된 감마 신호원의 일종인 라플라스 신호원의 경우에 다양한 분산 불일치에 대해, 양자기의 실제 왜곡을 수치로 구하였으며, 이 실제 왜곡과 두 근사식을 비교하였다. 제1차 및 2차 근사식은 모두, 설계 신호원의 분산에 대한 사용 신호원의 분산 비율이 클수록, 더 작은 양자점수에서도 실제 왜곡에 근접하였으며, 또 양자점의 개수가 64 이상일 때 실제 왜곡의 2~4% 이내의 오차를 보여, 높은 정확도를 갖는 것이 관찰되었다. 이를 종합할 때, 이 논문에서 제시하는 근사식들은, 수식이라는 측면과 정확도라는 측면에서, 가치있는 것으로 평가된다.

• 한국대기환경학회지
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• 제24권4호
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• pp.439-454
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• 2008

The purpose of this study was to extensively identify $PM_{10}$ sources and to estimate their contributions to the study area, based on the analysis of the $PM_{10}$ mass concentration and the associated inorganic elements, ions, and total carbon. The contribution of $PM_{10}$ sources was estimated by applying a receptor method because identifying air emission sources were effective way to control the ambient air quality. $PM_{10}$ particles were collected from May to November 2007 in the Yongin-Suwon bordering area. $PM_{10}$ samples were collected on quartz filters by a $PM_{10}$ high-volume air sampler. The inorganic elements (Al, Mn, V, Cr, Fe, Ni, Cu, Zn, Cd, Pb, Si, Ba, Ti and Ag) were analyzed by an ICP-AES after proper pre-treatments of each sample. The ionic components of these $PM_{10}$ samples ($Cl^_$, $NO_3^-$, $SO_4^{2-}$, $Na^+$, $NH_4^+$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$) were analyzed by an IC. The carbon components (OC1, OC2, OC3, OC4, OP, EC1, EC2 and EC3) were also analyzed by DRI/OGC analyzer. Source apportionment of $PM_{10}$ was performed using a positive matrix factorization (PMF) model. After performing PMF modeling, a total of 8 sources were identified and their contribution were estimated. Contributions from each emission source were as follows: 13.8% from oil combustion and industrial related source, 25.4% from soil source, 22.1% from secondary sulfate, 12.3% from secondary nitrate, 17.7% from auto emission including diesel (12.1%) and gasoline (5.6%), 3.1% from waste incineration and 5.6% from Na-rich source. This study provides information on the major sources affecting air quality in the receptor site, and therefore it will help us maintain and manage the ambient air quality in the Yongin-Suwon bordering area by establishing reliable control strategies for the related sources.

• 방사성폐기물학회지
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• 제9권2호
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• pp.73-80
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• 2011

한국방사성폐기물관리공단 주관 하에 개념 설계된, 연소도이득효과 적용 대용량 수송용기에 대해 방사선 차폐 안전성을 평가하였으며 여러 방사선원들이 수송용기 주변 선량률 분포에 미치는 영향을 분석하였다. 가능한 모든 방사선원(중성자선원, 감마선원, 방사화선원)들을 고려하였으며 보수적인 가상의 핵연료(너비: WH 17 RFA, 축방향: CE Type)를 선정, 실제 상황과 동일한 조건이 되도록 계산모델을 구축하였다. 모든 조건(정상 및 가상사고 조건)에서 표면선량률과 외부선량률이 법적기준치를 만족하고 있었으며 축방향 높이에 따라 각 선원들의 기여도가 변하고 있었지만 정상조건에서의 최대 표면선량률과 외부선량률은 방사화선원에 의한 영향이 가장 높은 것으로 확인되었다. 가상사고 조건에서는, 중성자선원의 선량률 기여도가 대략 90%에 달하고 있었으나 수송용기 끝단에서는 방사화선원에 의한 선량률이 급격하게 상승함에 따라 BUC 적용 수송용기의 방사선 차폐해석시 충분히 보수적으로 해석되도록 방사화선원을 정밀하게 분석하여 설정하여야 할 것으로 판단되었다.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2010년도 춘계학술대회 논문집
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• pp.334-335
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• 2010