• 대한안전경영과학회지
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• 제17권1호
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• pp.271-279
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• 2015

Global warming has pressured companies to put a greater emphasis on environment management which allows them to reduce environmental impact and costs of their operations. In Korea, the coal-fired power plants take a large account of electricity generation at 31.7% of the total electricity usage in 2014. Thus, environmental impact of coal-fired power plants is significant. This paper illustrated how to compute environmental impact and costs in electricity generation at a coal-fired power plant using MFCA methodology. Compared to the traditional accounting, an advantage of MFCA is to provide information on electricity generation costs and environmental wastes incurring throughout the production process of electricity. Based on MFCA, the coal-fired power plant was able to reduce production cost of electricity by 52.3%, and environmental wastes by 47.7%. As a result, MFCA seemed to be an effective tool in environmental management for power plants.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제3권1호
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• pp.7-12
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• 2022

Farming practices that balance environmental friendliness with biodiversity are increasingly valuable. Wild plants on farmlands compete for nutrients with crops and create a crucial microhabitat and resources for animals such as natural enemies. Investigating farmlands and their surrounding plants with limited human and material resources has become an essential aspect of evaluating the agricultural ecosystem services. This study investigated plants in six agricultural long-term ecological research sites in Taiwan from 2017 to 2020 to determine the ideal season for investigation. Cluster analysis was performed to group habitats with similar plant composition, and the species-area curves of the clusters in each season were created. The results indicated that the agricultural ecosystem could be divided into farmlands, banks, orchards, and tea gardens. The habitats were divided into farmland, bank, Chia-Yi orchard, Gu-Keng orchard, and tea garden clusters. Ground plant cover can be investigated all year with at least 18 quadrats. However, if human and material resources are limited, 10 quadrats should be the minimum for farmlands in autumn and for the other microhabitats in spring. The minimum number of quadrats is 10 for banks, 17 for orchards, and 9 for tea gardens.

• 생물환경조절학회지
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• 제30권3호
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• pp.196-205
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• 2021

본 연구는 대목 종류에 따라 나타나는 방울토마토 수량 차이를 생장상의 변화와 광합성 효율을 통해 비교분석하고자 수행하였다. 접수 '노나리'와 대목 4종류('파워가드', 'T1', 'L1', 'B.blocking')을 사용하여 접목한 4개의 처리구와 '노나리'를 접목하지 않은 1개의 처리구로 실험에 사용하였다. 방울토마토 생육후기인 5월의 주 당 평균 총 수확량을 조사한 결과 대목 'B.blocking'을 사용한 처리구는 417.5g으로 가장 높은 수확량을 보였고 대목을 사용하지 않은 처리구가 354.2g으로 가장 낮은 수확량을 보였다. 정식 252일 후의 개화위치를 조사한 결과 대목 'B.blocking'을 사용한 처리구는 14cm 내지 17cm의 개화위치를 보인 반면 대목을 사용하지 않은 처리구는 10cm 내지 14cm의 개화위치를 보였다. 정식 266일 후 생장강도를 조사한 결과 대목 'T1', 'L1', 'B.blocking'을 사용한 처리구는 10mm대의 생장강도를 보인 반면 대목을 사용하지 않은 처리구의 생장강도는 8.43mm로 낮은 값을 보였다. 대목을 사용한 처리구는 생육후기까지 생장의 균형을 맞춰 높은 수확량을 보인 반면 대목을 사용하지 않은 처리구는 세력이 저하되어 수확량이 감소한 것으로 판단된다. 엽록소 형광변수는 대목을 사용한 처리구가 대목을 사용하지 않은 처리구보다 높았다. 이상으로 방울토마토 접목묘를 사용하는 것이 생육후기까지 생장의 균형을 유지하고 광합성 효율이 높아 수량이 높은 것으로 판단된다.

• 한국재난정보학회 논문집
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• 제16권4호
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• pp.842-848
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• 2020

연구목적: 노후화된 발전기의 지속 가능한 운영을 위하여 효율적이며, 안전한 운영이 중요하다. 효율적 운영이란 경제적 관점이며, 안전한 운영은 발전 설비의 치명적 사고 발생에 대한 발생 이전의 사전 조치를 말한다. 그러므로 발전기의 지속가능 운영 모니터링을 위하여 관련된 센서 설치와 이를 기반으로 지속 가능에 대한 예측할 수 있는 모델에 대한 연구가 필요하다. 연구방법: 전기와 열에 대한 수요 예측, 엔진의 성능과 이상을 탐지하는 예측, 그리고 재 난 안전에 대한 예측 모델을 제시하였다. 이를 위하여 필요한 센서를 정의하였으며, 이를 기반으로 예측 모델을 각각 개발하여 수행하였다. 연구결과: 수요 예측 모델은 기존의 79%에서 90% 이상으로 예측 정확도를 향상시켰으며, 다른 2개 모델도 시스템의 지속가능한 안정적 운영을 지원하였다. 결론: 노후화된 발전설비의 지속가능 운영을 지원하기 위한 3가지 종류의 예측 모델을 개발하고 이를 제이비주식회사의 발전 설비에 실제 적용하여 운영하고 있다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2002년도 ICCAS
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• pp.66.4-66
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• 2002

In this paper, coefficient diagram method is applied to a center position controller design of the web. The significant property of this controller is the designer can design the controller simultaneously a good balance of stability, response, and robustness. Manabe's CDM is useless for designing high-order plant. We proposed a modified CDM which can be called as approximated pole placement method. The practicality of the proposed method is shown through computer simulation.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2000년도 추계 학술대회지
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• pp.177-178
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• 2000

• 전력전자학회:학술대회논문집
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.74-75
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• 2011

EBOP(Electrical Balance of Plant)는 연료전지 출력인 DC 전원을 전력변환기술을 이용하여 계통 전원에 연계하는 계통 연계 인버터 시스템이다. 포스코파워에서 개발한 3MW급 EBOP 시스템은 국제 규격(IEEE std.1547, UL1741)에 의한 성능 검증 시험을 거치고 국내 2개 현장에 5기를 적용하여 운전 중이다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 추계학술대회 논문집
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• pp.140-140
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• 2009

The polymer electrolyte membrane fuel cell(PEMFC) with the advantages of low-operating temperature, high current density, low cost and volume, fast start-up ability, and suitability for discontinuous operation becomes the most reasonable and attractive power system for transportation vehicle and micro-grid power plant in a household. 200W PEM-type FCs system was integrated by this study, then the electrical characteristics and diagnosis of the fuel cell were analyzed with variations on mass flow rate and stack temperature. The ranges of the variations are $20{\sim}70^{\circ}C$ on stack temperature and 1~8L/min on $H_2$ volume.

• Animal cells and systems
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• 제4권3호
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• pp.201-214
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• 2000

Two quite different types of plant cells are analysed with regard to transduction of the gravity stimulus: (i) Unicellular rhizoids and protonemata of characean green algae; these are tube-like, tip-growing cells which respond to the direction of gravity. (ii) Columella cells located in the center of the root cap of higher plants; these cells (statocytes) perceive gravity. The two cell types contain heavy particles or organelles (sataoliths) which sediment in the field of gravity, thereby inducing the graviresponse. Both cell types were studied under microgravity conditions ($10^{-4}$/ g) in sounding rockets or spacelabs. From video microscopy of living Chara cells and different experiments with both cell types it was concluded that the position of statoliths depends on the balance of two forces, i.e. the gravitational force and the counteracting force mediated by actin microfilaments. The actomyosin system may be the missing link between the gravity-dependent movement of statoliths and the gravity receptor(s); it may also function as an amplifier.

• 한국농공학회지
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• 제43권6호
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• pp.154-162
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• 2001

This study was performed to examine the rice growth and nutrient change in paddy soil with reclaimed sewage irrigation. Total nitrogen and total phosphorus in the experimental system were analyzed before and after rice culture. The experiment lasted three consecutive years, and this paper presents results of the last year. Additional supply of nutrients to the rice culture by reclaimed sewage irrigation was significant and it increased the yield. Nutrient uptake by rice plant increased with more nutrient supplied, however. there was limit in plant uptake. Nutrient accumulation occurred in the soil and it was more apparent for the phosphorus where most of the remaining quantity was accumulated while substantial amount of nitrogen was lost during the growing season. This study suggested that additional nutrient supply by reclaimed sewage irrigation might be a supplemental benefit to the rice culture, and it can help the fertilization management. However, long term effects of continual reclaimed sewage irrigation should be assessed carefully including nutrient mass balance in the paddy rice culture system.