• 한국지하수토양환경학회지:지하수토양환경
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• 제27권2호
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• pp.87-98
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• 2022

This study aims to prepare a technical protocol for identifying the source of nitrate in water using nitrogen (δ¹⁵N) and oxygen (δ¹⁸O) stable isotope ratios. The technical processes for nitrate sources identification are composed of site investigation, sample collection and analysis, isotope analysis, source identification using isotope characteristics, and source apportionment for multiple potential sources with the Bayesian isotope mixing model. Characteristics of various nitrate potential sources are reviewed, and their typical ranges of δ¹⁵N and δ¹⁸O are comparatively analyzed and summarized. This study also summarizes the current knowledge on the dual-isotope approach and how to correlate the field-relevant information such as land use and hydrochemical data to the nitrate source identification.

• 환경생물
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• 제35권4호
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• pp.452-460
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• 2017

내륙에 위치한 논 습지는 먼 거리를 이동하는 수조류들에게 풍부한 먹이원을 제공하는 중간기착지로, 도요물떼새류들의 보전에 매우 중요한 역할을 한다. 풍부한 대형저서생물들을 취식하는 도요물떼새류는 중간기착지에 따라 선호하는 먹이원을 쉽게 바꿀 수 있다. 그러므로 중간기착지에서 그들의 실제 먹이원을 확인하기 위해서는 취식지에 서식하는 잠재적 먹이원의 종류와 분포에 대한 정보가 매우 중요하다. 본 연구에서는 한국 중서부지역 논을 중간기착지로 이용하는 도요물떼새류의 먹이원을 확인하기 위해 당진군 석문면 난지도리에 위치한 농경지의 잠재적인 먹이원과 실제 먹이원을 확인하였고, 잠재적인 먹이원의 분포가 다양한 벼 재배활동에 의해 영향을 받는지 알아보았다. 그 결과 잠재적 먹이원은 총 10목 15과 19종의 대형저서생물로 나타났으며, 실제 먹이원은 대형저서생물에서 9목 9과로 나타났고, 미꾸리류나 새섬매자기 괴경도 섭식하는 것이 확인되었다. 또한 먹이원의 분포는 논갈이나 써레질과 같은 경작으로 형성된 토양의 상태와 농약 사용 유무에 의해 달라지는 것을 확인할 수 있었다. 특히, 먹이원의 종류(대형저서생물, 잔존볍씨, 씨앗)가 가지는 특성에 따라 세부적인 분포가 결정되는 것을 확인할 수 있었다. 이러한 정보들은 추후 논습지를 이용하는 도요물떼새류의 보전 관리에 중요한 기초 자료로 이용될 수 있을 것이다.

• 한국환경과학회지
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• 제20권6호
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• pp.755-765
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• 2011

Nitrous oxide ($N_2O$) is one of six greenhouse gases listed up in the Kyoto Protocol, and it effects a strong global warming because of its much greater global warming potential (GWP), by 310 times over a 100-year time horizon, than $CO_2$. Although such $N_2O$ emissions from both natural and anthropogenic sources occur, the latter can be controlled using suitable abatement technologies, depending on them, to reduce $N_2O$ below acceptable or feasible levels. This paper has extensively reviewed the anthropogenic $N_2O$ emission sources and their related compositions, and the state-of-the-art non-catalytic and catalytic technologies of the emissions controls available currently to representative, large $N_2O$ emission sources, such as adipic acid production plants. Challengeable approaches to this source are discussed to promote establishment of advanced $N_2O$ emission control technologies.

• 생약학회지
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• 제17권1호
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• pp.19-22
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• 1986

As a continuation of the previous work, a second group of sixty solvent fractions prepared from twenty plant species were screened for their inhibitory effects on adenosine 5'-diphosphate (ADP)-, arachidonic acid (AA)- or collagen-induced rat platelet aggregation. The results suggested that five plant species including Angelica koreana, Cassia obtusifolia, Gastrodia elata, Paeonia lactiflora and Salvia miltiorrhiza are potential sources of inhibitors of platelet aggregation.

• 한국초지조사료학회지
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• 제18권2호
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• pp.151-156
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• 1998

This study was conducted to evaluate the forage yield and quality of Fesrulolium bmunii(Festuca prafensis Huds. x Lolium multiflomm Lam.) as a forage sources. The experiment was arranged in a randomized block design with four replications from Sep. 1995 to May 1998 at Chungnam University. Treatments consisted of two forage species, Festulolium bmunii(Pau1ita) and Dactylis glomerc;d4Potomac). The dry matter yields, nutritive value, N and energy balance were observed. The yields of DM, CPDM and DDM per area(ha) were higher for Potomac (P< 0.01) than for Paulita. The content of CP showed no difference between Potomac and Paulita, but NDF, ADF and lignin contents of Paulita were absolutly lower than those of Potomac (P<0.05). The retained N and energy were also high for Paulita compare to for Potomac. It could be suggested that Paulita has higher potential for improvement of the forage quality than Potomac and it have a potential to provide as a forage sources.

• Nuclear Engineering and Technology
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• 제51권3호
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• pp.904-907
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• 2019

Nuclear energy remains one of the world's major energy sources, making up over 10% of global electricity generation in 2017. Public acceptance of nuclear energy is essential for its adoption. From a practical perspective, it is beneficial to have a simple indicator that can predict the actual adoption of nuclear energy. Based on practical experience, the authors suggest tolerance and self-sufficiency as potential indicators that may predict the adoption of nuclear energy. By evaluating the cross-sectional data of 18 countries in 2013, this research assesses the actual impact of tolerance and self-sufficiency on public acceptance in order to identify the validity of the two variables. The results indicate that the two variables are statistically significant, while public acceptance is insignificant in explaining national adoption of nuclear energy. This may be because tolerance reflects national willingness to accept potential risk, while self-sufficiency explains a government's likelihood of developing non-carbon energy sources.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 19-21 Oct. 1992
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• pp.187-192
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• 1992

There are several potential error sources that can affect the estimation of the position of an object using combined vision and acceleration measurements. Two of the major sources, accelerometer dynamics and random noise in both sensor outputs, are considered. Using a second-order model, the errors introduced by the accelerometer dynamics are reduced by the smaller value of damping ratio and larger value of natural frequency. A Kalman filter approach was developed to minimize the influence of random errors on the position estimate. Experimental results for the end-point movement of a flexible beam confirmed the efficacy of the Kalman filter algorithm.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 추계학술대회논문집
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• pp.482-488
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• 2000

This paper deals with a method to generate an acoustically bright zone that has a higher acoustic potential energ than the others. The acoustically bright zone can be generated by optimally excited multiple sources. A method to determine the volume velocity distribution of the sources was presented in this paper. For different applicative purpose, two kinds of cost functions are defined and through the eigenvalue analysis the optimal solution is obtained.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2005년도 추계학술대회 논문집
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• pp.170-172
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• 2005

• Environmental Analysis Health and Toxicology
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• 제19권2호
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• pp.227-233
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• 2004

The main objectives of this study were to identify from literature review the potential sources and to provide a preliminary national emission inventory for the unintentionally produced polychlorinated biphenyls (PCBs) (i.e., by - product PCBs). In Korea, fuel combustion, waste combustion, thermal industrial processes, and transportation were identified as potential sources of by -product PCB s. According to the availability of the emission factors and/or activity data, emission inventory could be assessed only for fuel combustion, waste combustion, steel industry, non-ferrous industry, and non-metallurgical industry. The total national emission of by-product PCBs was estimated to be 1087kg for the year 2000. The preliminary estimation further indicated that the steel manufacturing was the single dominant emission category, contributing 93％ to the total emission. Of the steel manufacturing processes, the contribution of the electric arc furnace was about 80％ of the total emission. Due to high uncertainty associated with both the emission factors and activity statistics, the emission estimates in this study are likely to contain significant errors. However, the results of the present work could serve the first step toward future efforts to establish national source and emission inventories of by-product PCBs.