• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2006.04a
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• pp.391-393
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• 2006

In this study, the performance of artificial neural network (ANN) models for estimating spatial distribution of water quality was evaluated using electric conductivity (EC) values in landfill site. For the ANN model development, feedforward neural networks and backpropagation algorithm with gradient descent method were used. In Test 1, the interpolation ability of the ANN model was evaluated. Results of the ANN model were more precise than those of the Kriging model. In Test 2, spatial distributions of EC values were predicted using precipitation data. Results seemed to be reasonable, however, they showed a limitation of ANN models in extrapolations.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.263-263
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• 2009

최근 정부의 녹색성장 정책과 RPS(Renewable Portfolio Standard)도입 계획에 따라 재생가능에너지 개발계획이 쏟아지고 있다. 특히 조력 발전의 경우, 시화, 가로림, 강화, 인천만 등 전 세계 최대 규모 타이틀을 서로 갱신하가며 서해바다를 중심으로 건설 계획이 집중되고 있다. 그러나 조수간만의 차이를 이용해 친환경 에너지원으로 인식되던 조력발전이 그 규모와 방식에 따라 환경파괴적 발전원으로 인식되고 있는 것도 현실이다. 갯벌소멸, 해양생태계 파괴, 해수면 상승 등 생태적 환경문제 야기와 더불어 지역 주민간의 사회환경적 갈등도 초래되고 있다. 본 논문은 국내 조력발전의 개발 계획과 과정을 살펴보고 생태적.사회적 환경영향 피해 점검을 통해, 바람직한 조력발전의 모습을 제시해 본다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.11a
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• pp.78-83
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• 2003

General algorithm is developed for the prediction of internal flow-induced noise. This algorithm is based on the integral formula derived by using the General Green Function, Lighthills acoustic analogy and Curls extension of Lighthills. Novel approach of this algorithm is that the integral formula is so arranged as to predict frequency-domain acoustic signal at any location in a duct by using unsteady flow data in space and time, which can be provided by the Computational Fluid Dynamics Techniques. This semi-analytic model is applied to the prediction of internal aerodynamic noise from a throttle valve in an automotive engine. The predicted noise levels from the throttle valve are compared with actual measurements. This illustrative computation shows that the current method permits generalized predictions of flow noise generated by bluff bodies and turbulence in flow ducts.

• Journal of the Korean Society of Visualization
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• v.11 no.2
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• pp.18-26
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• 2013

An accurate and reliable performance evaluation technique is indispensable for the development of marine antifouling coatings. The existing standard practice is however, based on the visual observation of biofouling settlement area, which is prone to the subjective judgment of the inspector. In spite of the above mentioned importance, a systematic and objective fouling evaluation technique has not yet been introduced. In this study, a novel quantitative antifouling performance evaluation method for marine antifouling paints is devised based on the image analysis of panel immersion test results. The present image analysis method is to quantify settlement area for each fouling category by distinctive color. The fouling categories are set as unfouled, biofilm, green algae, brown algae, calcareous animal and spongy animal with specific HSL (Hue, Saturation, Lightness) color ranges. In order to assess the effectiveness of the proposed method, static immersion tests for three antifouling coatings were undertaken for two years.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2005.11a
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• pp.127-139
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• 2005

It is very difficult to export the fresh agricultural products to long distant countries such as America and EU without any damage. Fresh exporting products would be met very hazardous environments such as hot and cold weather, heavy trembles with rolling and pitching. Therefore, care should be taken on tight fastening the products inside the container and keeping the designated temperature and relative humidity. The physical strength of outer box should be applied differently because each agricultural product has its own character for packaging. There have been many agricultural products researches for export packaging to the U.S.A. so far. However they have never got desirable results which enough to apply it in real. The main purpose of this research is to develop optimum compressive strength of corrugated fiber board box which would be used to American export packaging of fresh agricultural products such as perilla leaves, green red pepper and spinach.

• Korean Journal of Organic Agriculture
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• v.17 no.1
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• pp.35-53
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• 2009

The theme-type self-harvest concept proposed in this research will be applied as a relevant reference in planning and realizing urban-rural exchange facilities at the village level. The aim of this paper is to describe the concept, to characterize the self-harvesters and organic farmers involved, to illustrate the ecological, economic and social interaction and the possible constraints of the concept. What is more important, however, is to develop programs for consultants, organic farmers and green-minded consumers, to vitalize direct transaction. The proponents of self-harvest are convinced that this concept leads to ecological, economic and social benefits, which will help to design a sustainable food supply system for small, medium and large cities.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.167-168
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• 2000

The potential application of protoplasts useful for studies such as physiology, morphology, genetic engineering, etc has led to the development of suitable methologies for isolation and manupilation of protoplasts from a wide variety of algae (Waaland et al., 1990; Reddy and Fujita, 1991; Chen and Chiang, 1994). Protoplasts technology to seaweeds depends large on the ability to produce viable cells capable of regenerating into whole plantlets (Wakabayashi et al., 1999). Though Capsosiphon fulvescens is one of the important economic seaweeds culturing in Korea, surprisingly protoplasts approach on this species has not been reported so far. Consequently we investigated the various aspects related to the protoplasts of Capsosiphon fulvescens in this study. (omitted)

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.77-80
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• 2011

본 논문에서는 기존의 배전계통에 신에너지전원 연계로 인하여 발생하고 있는 정상상태와 전력품질에 대한 문제점을 LabVIEW를 이용한 신에너지전원 평가 시뮬레이터를 제작하여 분석한다. 종래의 배전계통에 있어서의 전력조류는 변전소에서 선로말단을 향한 단방향이었지만, 신에너지전원이 연계된 경우에는 그 출력용량의 여부에 따라 양방향의 전력조류가 발생할 가능성이 있어, 계통운용상 여러 가지의 문제점이 야기될 수 있다. 따라서 본 논문에서는 태양광전원 연계에 따른 정상상태와 전력품질에 대한 문제점을 상세히 분석하기 위하여, 실계통의 특성을 모의한 신에너지전원 평가 시뮬레이터를 제작하였다. 그리고 이 장치를 이용하여 역률, 선로길이, 태양광발전량의 변동에 따른 계통의 다양한 운용특성시험을 수행하여 제안한 평가 시뮬레이터의 유용성을 확인하였다.

• Proceedings of the KAIS Fall Conference
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• 2011.05a
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• pp.115-118
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• 2011

본 연구는 탄소발생 문제를 줄이는 방안을 개발하고자 LTE모형(친환경토지이용, 녹색교통, 녹색환경)을 3가지의 유형으로 나누어 각각의 유형에 해당되는 탄소저감방안을 개발하고 사례대상지에 적용하였다. 그리고 계획요소를 대상지에 맞게 도출 한 후 시뮬레이션을 하여 탄소저감의 효과를 분석 하였다. 도출된 기법을 연구 대상지에 적용한 결과 높은 저감효과를 보이는 요소를 도출할 수 있었고, 경미한 수준의 저감효과를 보이는 요소도 도출할 수 있었다. 탄소저감 비율은 25.51%이었고, 그중에서 특히 교통정온화 계획요소가 95.42% 압도적인 비율로 저감효과가 있음을 알 수 있었다.

• Journal of Korea Society of Digital Industry and Information Management
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• v.7 no.2
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• pp.9-17
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• 2011

In this paper, a bike management system using 900 MHz RFID technology has been developed. There are limits to the 13.56 MHz spectrum of existing management systems, which are single tag identification and the short possible identifying distance of the technology. In this paper, we use 900 MHz instead of 13.56 MHz in order to make wide recognition and multi-tag identification possible. Granted, there are also many benefits to using 13.56 MHz RFID tags, which include compatibility with existing bike management systems. This system was developed on the 900 MHz band using RFID similarly to existing 13.56 MHz systems in order to be able to manage multiple bikes at the same time.