• 에너지공학
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• 제18권1호
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• pp.22-30
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• 2009

본 논문에서는 산업체의 최근의 에너지를 둘러싼 문제점을 해결하기위해서 에너지다소비신고업체의 현황을 분석하고 산업체 업종별 전기와 열의 부하패턴 분석하여 가스열병합발전의 보급 확대를 위한 기반을 구축하였다. 즉, 경제성분석을 통하여 에너지다소비신고업체 중에서 가스 열병합발전으로 전환 가능한 잠재량 도출하여 우리나라 가스 및 전력수급에 미치는 영향을 분석하였다.

• 대한가정학회지
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• 제41권7호
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• pp.157-168
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• 2003

The purposes of this study were to explore the rural women's labor by measuring labor value economically. To achieve the purpose, this study applied four methods : replacement cost method individual function, replacement cost method generalist, opportunity cost method and shadow wage method. The results of this study were as follows: 1) Time used for agricultural work and household work by with women were 5.3 hours and 3.8 hours each. 2) According to the methods used, the amounts of valuing rural women's labor were varied and ranged from 23,000 won to 43,000 won per day. This study might help recognize the degree of rural women's labor contribution to the household income of farm households and improve the socio-economic status of rural women through showing the productivity of the rural women's labor.

• 자원ㆍ환경경제연구
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• 제22권1호
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• pp.77-98
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• 2013

본 논문에서는 향후 포스트 교토협약에서 온실가스 감축의무국으로 분류될 가능성이 높은 세계 최대의 $CO_2$ 배출국 중국의 화력발전산업을 대상으로 Shephard 투입물거리함수를 추정하여 $CO_2$ 암묵가격과 기술효율성, 그리고 투입요소 간 간접 모리시마 대체탄력성을 측정한다. 1981-2009년 기간 동안 $CO_2$ 1톤을 감축하는 데 연간 평균 약 3.2달러의 비용이 드는 것으로 나타났다. 이는 한국, 일본의 발전 산업에 대한 $CO_2$ 암묵가격 추정치보다 낮은 수준으로서 향후 이들 나라와 배출권 거래가 이루어질 경우 배출권 판매를 통한 경제적 이득이 예상된다. 기술효율성의 향상으로 달성할 수 있는 최대 $CO_2$ 잠재 감축량은 연간 평균 약 2천 5백만톤에 이르는 것으로 산정되었다. 석탄과 석유 등의 연료와 자본은 상호 대체가능하며 자본이 연료를 더 용이하게 대체하는 것으로 나타났다.

• 전자공학회논문지D
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• 제34D권11호
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• pp.90-100
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• 1997

In this paper, we propose a new optical thresold generator as a key-stream genrator for stream cipher systems. The random key-bit stream is generated by a digital generator that is composed of LFSRs and nonlinear ligics. Digital implementatin of a key-stream generator requires large memory to implement programmable tapping points. This memory problem may be overcome easily by using the proposed optical system which has the proberty of 2D parallel processing.To implement hte threshold generator optically, we use conventional twisted nematic type SLMs (LCDs). This proposed system is based on the shadow casting technique for the AND operation between taps and sregister stages. It is also based on the proposed PMRS method for modulo 2 addition. The proposed PMRS method uses the property of light's polarization on LCD and can be implemented optically using one LCD and some mirrors. One of the major advantages of the proosed system is that there is no limitation of the number of the progarmmable tapping points. Therefore, the proposed system can be applied for the 2D encryption system which processes large amounts of data such as 2D images. We verify the proposed system with some simulation.

• 한국환경과학회지
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• 제18권9호
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• pp.1011-1015
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• 2009

The vegetated porous pavement can be installed as an alternative way to replace the traditional pavement, which contributes less to the water circulation system in the urban area. This study aims to an investigation based on the shadow and pressure of the vehicle system, where the turfgrass get grown and the green block get constructed on the grassy parking lot. This study might achieve these conclusions, in the case of use 'green block' makes grass parking lot, plant a kind of 'zenith' and takes sod thickness 40 mm are more efficient for turfgrass growth in the early times. In the case of parking over 8 hours in a day, after 5 weeks turfgrass growth would come into reduce. So over 4 hours parking and after 9 weeks, we need consider to setting up green block in grassy parking lot. The grassy ground would get pressured by the vehicles' load and it would bring into some damage due to the load after 3 weeks. So we should put the grass's growth root point under the designed a top of 'green block' level. When the vehicle amounts and parking density is in a low level, it could be an environmentally friendly product.