• 한국환경과학회지
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• 제27권10호
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• pp.907-923
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• 2018

The aim of this study was to determine the appropriate stockpiling methods for revegetation by comparing the germination status of seed banks before and after preservation for 2 years. Soil temperature in stockpiled topsoil was higher in open treatment and at 1.5 m, whereas soil water content was maintained at lower levels (14.06-19.08%), than those in the control group. The seed banks in stockpiled topsoil had 48 species and 1,559 individuals, among which perennials showed the highest number in terms of life forms, whereas Compositae and Gramineae were dominant in terms of families. Based on seed bank type, persistent seed banks had the highest number of species, while transient seed banks had the highest number of individuals. By stockpiling period, the number of species in the seed bank started to increase after 24 months, while the number of individuals began increasing after 12 months and exceeded that of the control group after 24 months. Regarding the treatment of stockpiling methods, the number of species and individuals in open treatment were closer to those of the control group. When analyzed by height, the number of species and individuals were higher at 0 m, but still lower than those of the control group. A multivariate analysis of variance (MANOVA ) showed that the optimal combination was obtained in open treatment and the number of individuals increased with the lengthening of the stockpiling period.

• 한국토양비료학회지
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• 제45권1호
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• pp.43-50
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• 2012

Two typical animal waste management practices, composting and stockpiling, were evaluated for their effect on the degradation of three veterinary antibiotics (VAs), chlortetracycline (CTC), tylosin (TYL), and monensin (MNS). The VAs were applied to horse manure plots subject to composting or stockpiling, and core samples were collected over a period of time. Selected buffer solutions were used to extract the VAs and analysis for concentration was conducted with solid phase extraction (SPE) followed by high performance liquid chromatography tandem mass spectrometry (HPLC/MS/MS) technique. The VAs demonstrated rapid dissipation within ten days followed by a gradual decrease in concentration until the end of the experimental period (141 days). All three VAs degraded more rapidly in the composting samples than in the stockpiling samples, particularly between 20 and 60 days of the observation period. Degradation of the three VAs generally followed a first-order kinetic model, and a fitted model with a calculated rate constant was determined for each treatment. TYL in composting showed the fastest degradation, with a calculated rate constant of $0.91day^{-1}$; the slowest degradation was exhibited by MNS in stockpiling, with rate constant of $0.17day^{-1}$. Calculated correlation coefficients ranged from 0.89 to 0.96, indicating a strong correlation between measured concentrations and fitted values in this study. Although concentration of TYL in composting treatment showed below detection limit during the test period, this study suggests that composting can reduce animal waste contaminants prior to field application as fertilizer.

• 자원ㆍ환경경제연구
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• 제13권2호
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• pp.301-322
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• 2004

기존 석유비축사업은 안보 위주의 정태적(stock) 개념에 바탕을 둔 것으로 최근의 여건 변화에 따라 경제성 위주의 동태적(flow) 개념으로 전환될 필요성이 대두되고 있다. 본 연구에서는 석유비축의 경제성 제고 방안으로서 유가시황에 따라 베이시스를 활용한 선택적 거래전략을 제시하고, 이들 거래전략의 효과를 정량적으로 분석하였다. 이를 위해, WTI 유종을 대상으로 1997년 10월~2002년 8월에 해당하는 주간 현물가격과 선도가격을 활용하여 선택적 거래의 유용성을 검증하였다. 분석결과를 요약하면, 유가상황을 고려하지 않는 경우에 비해 선택적 거래가 수익의 기대값을 향상시키고, 이의 변동성을 감소시킬 수 있다. 또한, 선택적 거래에서도 실행수준을 고려하여 다시금 선택적으로 거래하는 경우가 수익의 기대값을 증가시키고 위험을 감소시킬 수 있다. 이상의 분석결과를 토대로, 비축시설과 비축유를 적극적으로 활용함과 동시에 적절한 형태의 파생상품거래를 병행하는 것이 국내 석유비축사업의 경제성을 제고하는데 도움이 될 것으로 판단된다.

• 대한원격탐사학회지
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• 제38권4호
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• pp.365-374
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• 2022

Mining activity causes environmental pollution and geological hazards such as ground subsidence or landslide of which continuous monitoring is necessary. In this study, the activity on the Fushun West Open-Pit Mine (FWOPM), one of the largest open-pit coal mines in Asia located in Fushun, Liaoning Province, China, was analyzed by using a time-series Sentinel-1 InSAR coherence dataset. By using the difference between the two Digital Elevation Models (DEM) of the area, it was possible to confirm that there was a stockpiling activity in the western area of the FWOPM while excavation activity in the eastern area. By using RGB composite images using the yearly-averaged InSAR coherence images, the activity of the mine was confirmed by period, which was confirmed by Google Earth optical images. As a result, it was possible to confirm three landslides and the related activities on the northwest slope and the dumping activity on the west slope of FWOPM.