• 방사성폐기물학회지
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• 제18권2_spc호
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• pp.317-325
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• 2020

한국원자력환경공단은 처분시설 내 1단계 인수·저장구역의 인수검사 공간 및 드럼 취급 공간 부족에 대한 문제를 해결하기 위하여 방폐물검사건물을 건설하여 저장·처리능력을 확충할 예정이다. 본 연구에서는 MCNP 코드를 이용하여 방폐물검사건물 내 저장구역에서 취급하는 해체 방사성폐기물 대상 신형처분용기를 대상으로 작업종사자의 피폭선량을 평가하였다. 평가결과, 시설 내 저장 가능한 최대 용기 개수(304개)와 방사선작업에 대한 연간 예상 작업시간(약 306시간)에 대하여 연간 집단선량은 총 84.8 man-mSv로 계산되었다. 시설 내 총 304개의 신형처분용기(소형/중형 타입)가 저장 완료된 시점에서 인수검사, 처분검사를 위한 작업종사자의 투입인력은 총 25명, 작업종사자 당 예상피폭선량은 연평균 3.39 mSv로 산출되었다. 소형용기 취급 시 작업종사자의 고방사선량 작업에 따른 작업효율과 방사선적 안전성 확보를 위해서는 콘크리트 라이너의 두께를 증가시키는 추가적인 차폐가 필요할 것으로 평가되었다. 향후 본 연구를 바탕으로 실측기반의 해체폐기물의 선원항과 특성을 활용하여 방사선작업 당 작업시간 및 투입인력을 산출함으로써 작업종사자의 최적의 방사선작업조건을 도출할 수 있을 것으로 사료된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제10권6호
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• pp.75-80
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• 2005

남한강 상류지역의 금속광산인 거도, 만정, 조일광산은 1988년 석탄광산합리화 사업과 더불어 폐광되었으며, 휴$\cdot$폐광된 이후 다량의 광산 폐기물을 방치하여 주변환경을 오염시키고 있는 실정이다. 그러나 광미, 폐석 등의 이동에 의한 주변의 토양오염에 대한 정량적 평가가 없기 때문에 이들 광산폐기물에 의한 오염정도를 확인하기 어렵다. 따라서 폐광된 거도, 만정, 조일 광산의 광산 폐석에 의한 수질 오염 가능성 평가를 위해 각 광산에서 폐석 시료를 채취하였으며, HCl 처리 농도에 따라 지화학적 농축 계수(Index of geoaccumulation), 중금속 존재 형태와 이동성에 관하여 조사하였다. 카드뮴, 납, 아연, 구리, 니켈 그리고 크롬의 지화학적 농축 계수는 각각 6, $4\~6,\;0\~6,\;4\~5$, 2, 0을 나타냈다. 광산 폐석에서 카드미뮴, 납, 아연, 구리의 지화학적 농축계수 분석을 통하여 이러한 지역이 상당한 오염 가능성을 알 수 있었다. 광산 폐석에서 중금속의 존재 형태는 구리의 경우 유기물 형태, 납은 탄산염 형태, 니켈과 아연은 잔류상 형태로 나타났다.

• 한국지리정보학회지
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• 제17권3호
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• pp.54-67
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• 2014

본 연구는 RapidEye 영상을 활용하여 2013년 발생한 대형산불 피해지역(울주, 포항, 봉화)을 대상으로 온실가스 배출량 추정하였다. 온실가스 배출량 추정은 2006 IPCC(Intergovernmental Panel on Climate Change) 가이드라인에서 제시하는 추정식을 이용하였다. 본 연구에서는 최대 우도법을 기반으로 한 감독분류를 실시하여, 산불피해지역의 강도등급 및 피해면적을 산출하였으며, 현장정보와 비교하여 정확도 검증을 실시하였다. 산불피해 등급별 정확도 평가 결과는 평균적으로 전체정확도 73.93%과 Kappa 계수 0.67로 나타났다. 2013년 대형산불피해지의 온실가스 배출량 추정은 울주지역 $CO_2$ 63,260, CO 5.207, $CH_4$ 360, $N_2O$ 28.0, $NO_x$ $4.4g/kg^{-1}{\cdot}ha^{-1}$, 포항지역 $CO_2$ 28,675, CO 2.359, $CH_4$ 163, $N_2O$ 12.7, $NO_x$ $1.9g/kg^{-1}{\cdot}ha^{-1}$ 그리고 봉화지역 $CO_2$ 53,086, CO 1,655, $CH_4$ 114, $N_2O$ 23.5, $NO_x$ $3.6g/kg^{-1}{\cdot}ha^{-1}$로 나타났다.

• 한국지구과학회지
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• 제23권8호
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• pp.666-675
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• 2002

본 연구에서는 자기 주도적 학습을 위한 웹기반 수준별 학습 자료를 설계 ${\cdot}$ 개발하고 이를 현장에 적용하여 그 효과를 검증하고자 하였다. 이를 위하여 제7차 교육과정 고등학교 과학10의 ‘일기와 기후’ 단원을 기본 학습자료와 심화 ${\cdot}$ 보충형 학습자료로 설계 ${\cdot}$ 개발하고 이를 적용하여 그 효과를 전통적 수업과 비교한 결과는 다음과 같다. 첫째, 웹 기반수준별 학습은 전통적 수업보다 학생들의 자기 주도적 학습특성 중 자아개념, 학습열성, 미래지향성, 창의성, 자기 평가력에 긍정적인 효과를 나타내었으며 이는 학습자가 주어진 학습체제와의 다양한 교류를 통하여 필요한 정보와 지식을 획득하는 웹 학습의 특성 때문인 것으로 보인다. 웹 기반 수준별 학습이 자기 주도적 학습특성에 미치는 효과를 학습능력별로 살펴본 결과, 학습자의 학습능력 수준에는 무관한 것으로 나타났다. 둘째, 웹 기반 수준별 학습은 전통적 수업보다 학생들의 과학성취도에 긍정적인 효과를 나타내었으며 학습능력 수준이 중위이상인 학습자들에게 더 효과적이었다. 이러한 연구의 결과를 고려할 때, 하위수준 학습자들의 학업성취도를 높이기 위해서는 보충학습의 내용을 더 구체적으로 구성하고 경로 면에서 학습자 편의성을 높이는 웹 설계가 필요하다. 셋째, 웹 기반 수준별 학습에 대한 학습자들의 인식 결과를 보면 시각적 효과와 화면 구성에 대하여 긍정적인 평가를 하였다. 또한 학습 경험을 계획하고 필요한 자원을 자신만의 경로로 찾아서 학습하는 자기 주도적 학습이 수준별 학습에 긍정적인 효과를 미치는 것으로 응답하였다.

• 한국과학교육학회지
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• 제21권3호
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• pp.473-486
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• 2001

본 연구는 과학 실험활동을 중심으로 구성된 학교 외 과학 행사를 명가하는 데 목적을 두고 있다. 1998년도 '신나는 과학 놀이마당'에 참석한 857명 중 무작위로 표집한 121명의 초 중등 학생과 행사계획 및 진행을 담당한 72명의 지도 학생과 19명의 지도교사를 대상으로 사전-사후 설문조사와 관찰을 통하여 프로그램의 평가 결과를 분석하였다. 프로그램에 대한 평가는 1) 행사목표의 달성수준, 2) 행사 구성/운영의 적합성, 3) 행사 진행과정의 효율성, 4) 행사의 사전 안내 및 참석 학생과 지도학생의 참석동기의 세부항목으로 구분하였다. 대부분의 참가학생, 지도학생, 지도교사는 프로그램의 전반에 걸쳐 높은 만족도를 보였다. 평가 결과에 따른 프로그램의 개선점은 참가학생들이 보다 더 적극적으로 참여하는 과학 활동을 제공하고, 탐구력을 더욱 강조하는 활동과 일상생활과 관련되는 과학 내용을 더 많이 포함하도록 계획되어야 하는 점이다. 또한, 행사에 대한 사전 안내 및 광고를 보다 효율적으로 추진하여야 하며, 지도학생들의 참가학생에 대한 효율적인 학습-교수 전략을 개발하고, 지도교사-지도학생간의 상호협력도 향상되어야 할 것이다.

• 한국식품위생안전성학회지
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• 제26권3호
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• pp.266-272
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• 2011

The safety of liquid-type herbal preparations (47 samples) and beverages containing herbal medicines (18 samples), which are distributed in Gyeonggi province was studied by analyzing heavy metals, benzo(a)pyrene, preservatives and sugar content and to explain the differences between medicine and food based on the labeling standards. The herbal preparation is regarded as medicine and can be differentiated from the beverages containing herbal medicine, which is food, based on the fact that the herbal preparation should be labeled with usage, dosage, efficiency and effect. The mean concentrations of Pb, As, Cd, Hg were found to be 0.014 mg/kg, 0.113 mg/kg, 0.004 mg/kg and 0.003 mg/kg in herbal preparation and 0.009 mg/kg, 0.122 mg/kg, 0.003 mg/kg and 0.002 mg/kg in beverages containing herbal medicines, respectively. In 10 cases of herbal preparations and 6 cases of beverages containing Rehmanniae Radix Preparata (Sukjihwang), benzo(a)pyrene was not found. According to preservative test on herbal medicine, dehydroacetic acid was found less than the indicated content in 6 cases out of 37 cases, which labeled with preservatives, and benzoic acid, dehydroacetic acid and methylparaben were contained with 164.0~198.0 mg/kg, 149.8~272.5 mg/kg and 88.4 mg/kg, respectively, in 3 cases out of 10 cases, which was not labeled with preservatives. Among 16 cases of beverages containing herbal medicines, 3 cases of preservative-labeled beverages had the preservatives, and the rest of all, which was not labeled with preservatives, did not show that they contain any preservative, therefore, it was suitable for the labeling standards. As a result of sugar content test, preservative-labeled products were not appreciably different from the others.

• 한국대기환경학회지
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• 제30권6호
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• pp.586-599
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• 2014

During the last two decades, indoor air quality and volatile organic compounds (VOCs) have been of concern in Korean society due to their nature of potential health impacts. In order to investigate the pollution levels of VOCss in indoor environments, establishment of a solid test method for monitoring the airborne VOCss is essential. In Korea, a method based on adsorbent sampling and GC analysis coupled with thermal desorption was proclaimed as the Korea Standard Method for Indoor Air Quality Test. This study was carried out to examine some inherent problems of the VOCs measurement method. The VOCs method does not describe in detail preparing the standard samples. The standard samples may be prepared by impregnation of either liquid standard solutions or a mixture of standard gases. In this study, we investigated the optimal temperature condition for transferring the liquid standards onto a standard adsorbent tube. As a result, keeping the impregnation temperature at $250^{\circ}C$ will be recommended in regard of the boiling points of multiple target analytes and the thermal stability of the adsorbent. We also demonstrated some problems associated with handling of a syringe used for transferring the standard solutions onto the adsorbent tubes, and a best way to get rid of the syringe problems was suggested. Finally, a number of field works were conducted to evaluate the performance of adsorbent sampling methods. Comparison of different adsorbent tubes, i.e. tube packed with single sorbent (Tenax) and double sorbents (Tenax with Carbotrap), revealed that 30 to 40% differences between the two groups, implying that sampling efficiency is depending on the volatility and the strength of adsorbents. However, duplicate precisions for VOCs sampling with a same type of adsorbent and at same flow rates appeared to be satisfactory to be all within 20%, which is a quality control guideline. Distributed volume precisions were also found to be within a guideline value, 25%, although the precision was in general inferior to the duplicate precision. The Korea indoor VOCs test method should be more refined and improved in many aspects, particularly procedure and instrumentation for preparing the standard samples and specification of quality control assessment.

• 동의생리병리학회지
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• 제18권4호
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• pp.1001-1006
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• 2004

In order to examine the anti-arthritic properties of ShinEumHur(SEH)-herbal acupuncture, an adjuvant-induced arthritic rat was generated by the intra-articular injection of dried cells of Mycobacterium tuberculosis emulsified in squalene into the right knee joint. Fifty microliter of SEH extract was injected into Zusanli(ST36) acupoint on the ipsilateral hind paw every other day for 2 weeks. The body weight, knee circumference, squeak threshold, and weight distribution ratio were analyzed as the assessment methods addressing arthritic symptoms such as arthritic pain, edema, and tenderness. The weight distribution ratio was measured by a digital-type analgesia instrument using the dual channel scale that separately measures the weight the arthritic rat distributes to each hind paw, and thus quantifies both of swelling and pain severities at once. The therapeutic effects of SEH-herbal acupuncture, assessed by squeaking threshold and weight distribution ratio, were observed on 8th day after the arthritis induction as compared to saline group and control group. On 10th day, SEH-herbal acupuncture therapy significantly started to alleviate the growing pattern of knee circumference of an arthritic rat in the range of 0.2㎝. However, the loss of body weight was not significantly recovered. Taken together, the SEH-herbal acupuncture exhibited the significant therapeutic efficiency to treat adjuvant-induced monoarthritis in rat.

• 한국물환경학회지
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• 제24권2호
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• pp.185-194
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• 2008

There is increased soil erosion potential at highland agricultural crop fields because of its topographic characteristics and site-specific agricultural management practices performed at these areas. The agricultural upland fields are usually located at the sloping areas, resulting in higher soil loss, pesticides, and nutrients in case of torrential rainfall events or typhoon, such as 2002 Rusa and 2003 MaeMi. At the highland agricultural fields, the soil reconditioning have been performed every year to decrease damage by continuous cropping and pests. Also it has been done to increase crop productivity and soil fertility. The increased amounts of soil used for soil reconditioning are increasing over the years, causing significant impacts on water quality at the receiving water bodies. In this study, the field investigation was done to check soil reconditioning status for potato, carrot, and cabbage at the Doam-dam watershed. With these data obtained from the field investigation, the Soil and Water Assesment Tool (SWAT) model was used to simulate the soil loss reduction with environment-friendly and agronomically enough soil reconditioning. The average soil reconditioning depth for potato was 34.3 cm, 48.3 cm for carrot, and 31.2 cm for cabbage at the Doam-dam watershed. These data were used for SWAT model runs. Before the SWAT simulation, the SWAT ArcView GIS Patch, developed by the Kangwon National University, was applied because of proper simulation of soil erosion and sediment yield at the sloping watershed, such as the Doam-dam watershed. With this patch applied, the Coefficient of Determination ($R^2$) value was 0.85 and the Nash-Sutcliffe Model Efficiency (EI) was 0.75 for flow calibration. The $R^2$ value was 0.87 and the EI was 0.85 for flow validation. For sediment simulation, the $R^2$ value was 0.91 and the EI was 0.70, indicating the SWAT model predicts the soil erosion processes and sediment yield at the Doam-dam watershed. With the calibrated and validated SWAT for the Doam-dam watershed, the soil erosion reduction was investigated for potato, carrot, and cabbage. For potato, around 19.3 cm of soil were over applied to the agricultural field, causing 146% of more soil erosion rate, approximately 33.3 cm, causing 146% of more soil erosion for carrot, and approximately 16.2 cm, causing 44% of more soil erosion. The results obtained in this study showed that excessive soil reconditioning are performed at the highland agricultural fields, causing severe muddy water issues and water quality degradation at the Doam-water watershed. The results can be used to develop soil reconditioning standard policy for various crops at the highland agricultural fields, without causing problems agronomically and environmentally.

• 한국물환경학회지
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• 제29권3호
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• pp.365-376
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• 2013

The purpose of this study was to evaluate effects of spatio-temporal changes in land uses and rainfall magnitude using the Soil and Water Assessment Tool (SWAT). Prior of application of the model to real-world problem, the model should be calibrated and validated properly. In most modeling approaches, the validation process is done assuming no significant changes occurring at the study watershed between calibration and validation periods, which is not proper assumption for agricultural watersheds. If simulated results obtained with calibrated parameters match observed data with higher accuracy for validation period, this does not always mean the simulated result represents rainfall-runoff, pollutant generation and transport mechanism for validation period because temporal and spatial variables and rainfall magnitude are often not the same. In this study SWAT was applied to Mandae study watershed in Korea to evaluate effects of spatio-temporal changes in landuses using 2009 and 2010 crop data for each field at the watershed. The Nash-Sutcliffe model efficiency (NSE) values for calibration and validation with either 2009 or 2010 was evaluated and the NSE value for calibration with 2009 and calibration with 2010 were compared. It was found that if there is substantial change in land use and rainfall, model calibration period should be determined to reflect those changes. Through these approaches, inherent limitation of the SWAT, which does not consider changes in land uses over the simulation period, was investigated. Also, Effects of changes in rainfall magnitude during calibration process were analyzed.