• Transactions of the Korean Society of Mechanical Engineers B
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• v.39 no.4
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• pp.317-324
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• 2015

In this study, a solar thermal system is designed to provide hot water and electricity for improvement of solar thermal energy availability in an apartment complex. The electricity is generated with Organic Rankine Cycle (ORC) by the solar thermal energy. R134a, R141b and R245fa are selected for operating fluid of the solar thermal ORC system. ORC with R245fa shows the best performance based on the variation of pressure. The irreversibility of component showed that the technology advance of the evaporator ensures a performance improvement. The sensitivity study results indicate that the turbine performance is most effective way to improve the performance of ORC system. An economic analysis showed that approximately 50% more income could be achieved by a solar thermal ORC system with a hot water supply.

• 한국벤처창업학회:학술대회논문집
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• 2017.04a
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• pp.21-21
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• 2017

귀농귀촌 문화가 유행하고 농업의 미래 가치에 대한 인식이 변화되면서 농산업으로의 새로운 진출을 계획하는 인구가 늘고 있다. 우리의 농업은 자급자족경제로부터 상업경제로 발전되어 왔고, 글로벌 시장 개방 및 생산 기술의 지속적 발전으로 공급이 수요를 초과하며 가격이 점점하락하는 추세를 보이고 있다. 농업 현장의 여러 어려움에도 불구하고 농산업의 긍정적인 여건들도 형성되고 있다. 올바른 먹거리를 추구하는 식품 소비패턴의 변화, 환 생태 치유 자연에 대한 소비자의 관심고조, 스마트 팜과 같은 생산환경의 자동화, 지역 자원을 근거한 공동경영체 운영 등과 같은 현상이 두드러지게 나타나고 있다. 이러한 시점에 농산업분야에 새로이 진출하고자 하는 개인 또는 소규모 사업주체들은 자신의 사업에 대한 정체성을 이해하고, 효율적인 사업운영을 위한 차별화 전략을 확보할 필요가 있다. 본 연구는 개별 또는 소규모 조직의 농업인과 예비농업인들이 자신의 사업에 대한 정체성을 이해하고, 사업운영을 위한 전략 선택을 돕는 비즈니스모델 템플릿 개발을 목표로 하였다. 이를 위해 농업 전문가, 창업 전문가, 비즈니스모델 전문가 풀을 구성하여 농산업 특성을 이해하고 최근 농업 농촌에서 이슈가 되고 있는 농업비즈니스 트랜드를 분석하였다. 근거 자료 및 전문가 토론을 통해 농산업 비즈니스를 '시장가치 추구형', '사회적가치 추구형', '연대하는 시장가치 추구형', '연대하는 사회적가치 추구형'의 4가지 유형으로 구분하고, 각 유형별 사례기업을 조사하여 비즈니스모델을 분석하였다. 비즈니스모델은 비즈니스모델 젠 캔버스를 이용하여 표현하였다. 비즈니스모델 젠은 비즈니스 유형에 따라 일반 창업형, 협동조합형, 임팩트비즈니스형 등 차별화된 캔버스 모델을 제공하고 있으며, 고객중심의 비즈니스 관점을 보다 세밀히 제공하는 툴이다. 본 연구에서는 비즈니스모델 젠을 통해 4가지 유형의 농산업 비즈니스 모델을 분석하였다. 본 연구의 결과는 농산업에 진출하는 사업주체의 사업진행 방향 및 전략선택을 위한 교육 컨설팅 현장에서 널리 이용될 수 있을 것으로 판단된다.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.2028-2032
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• 2009

하천법에서 하천유지유량은 "생활 공업 농업 환경개선 발전 주운 등의 하천수 사용을 고려하여 하천의 정상적인 기능 및 상태를 유지하기 위한 최소한의 유량"으로 정의 되어있고, "하천유지유량 산정요령"에 따라 갈수량을 기본으로 하여 하천의 수질보전, 하천 생태계 보호, 하천경관 보전 등 8가지 항목을 고려하여 산정하고 있다. 환경부에서는 2007년1월 환경부 고시에 '중권역별 수질 및 수생태계 목표기준과 달성기간"을 제정 고시하였고, 하천의 주요지점에 목표수질을 설정하고 그 수질을 만족시키기 위해 오염물질의 허용량을 제한하는 오염총량관리제도를 도입하였다. 이와 같이 하천 수질의 중요성이 대두되고 있으며, 하천의 기능을 제대로 유지하기 위해서는 수량뿐 아니라 적절한 수질이 요구 된다. 본 연구에서는 한국건설기술연구원과 SEI-US(Stockholm Environment Institute-U.S center)가 공동으로 개발한 통합수자원평가모형인 K-WEAPq 모형을 이용하여 만경강 유역의 네트워크를 구축하고 2003년의 수질 및 유량 자료를 이용하여 수량-수질을 모의하였다. 일별 수량-수질 동시모의를 통해 만경강 유역의 하수처리장 방류수 수질에 따른 하천 수질의 연중 변화를 파악하였고, 하수처리장 방류수의 수질을 변화시켜 수질모의 결과를 비교하였다. 분석결과 하수처리장 방류수의 수질에 따라 하천의 수질이 변화됨을 알 수 있고, 하수처리장 방류수 농도를 적절하게 조절하여 하천의 목표수질을 달성할 수 있음을 알 수 있다. 이 결과를 활용하면 하천의 수질 및 유량에 따라 하수처리장의 효율적인 운영이 가능하며 비용절감의 효과를 기대할 수 있을 것이다.

• Journal of the Korean Institute of Gas
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• v.11 no.1 s.34
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• pp.40-45
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• 2007

This paper describes NDIR $CO_{2}$ gas sensor that shows the characteristics of temperature compensation. It consists of novel optical cavity that has two elliptical mirrors and a thermopile that includes ASIC chip in the same metal package for the amplification of detector output voltage and temperature sensor. The newly developed sensor module shows high accuracy ($less\;than {\pm}40\;ppm$) throughout the measuring concentration of $CO_{2}$ gas from 0 ppm to 2,000 ppm. After implementing the calculation methods of gas concentration, which is based upon the experimental results, the sensor module shows high accuracy less than ${\pm}5\;ppm$ error throughout the measuring temperature range ($15^{\circ}C\;to\;35$^{\circ}C$) and gas concentrations with self-temperature compensation.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.499-503
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• 1989

Relatively little is known about the antigenic relatedness of the different developmental stages of Cryptosporidium. A monoclonal antibody (mAb), an IgG3, was produced against the Cryp-tosporidium merozoite stage by immunizing mice with merozoite preparation. This monoclonal was reacted with sporozoite antigens in Western blotting resulting in recognition of an epitope on a 3.5-kDa antigen. An immunoelectron microscopic technique was used to investigate the antigenic relatedness of Cryptosporidium Sporozoites and merozoites. Mouse intestine was fixed with 1 ％ glutaraldehyde and embedded in LR White. Thin sections were then sequentially treated with murine IgG3 mAb and anti-mouse IgG conjugated to 15-nm diameter colloidal gold. This mAb showed similar (sur-face/cytoplasmic) immunoelectron microsropic colloidal gold labeling patterns with sporozoites and merozoites, indicalting epitope sharing between these two stages. This information might be useful for identifying possible epitopes to which a vaccine could be developed.

• Journal of the Korean association of regional geographers
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• v.9 no.4
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• pp.592-607
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• 2003

This study on land use and regeneration of urban central district in Daegu investigates the current trend of those changes, and examines the change of urban core on land use, Since the 1980s, large cities in Korea have experienced the decline of spatial economic activities as well as population. Such urban decline has a relation with land use which can be classified with urban land use district and actual land use. This study tried to capture urban land use in three aspects; downtown business, residence, and the change of land use conversion. Based on land use characteristics, the size of residence land use has played a major role in hindering of the efficiency of land use. Also, this study has reviewed urban renewal projects in Daegu, especially urban core renewal projects, and discussed the problems of the projects.

• Journal of Satellite, Information and Communications
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• v.1 no.2
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• pp.32-37
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• 2006

ETRI has been developing the Ka-band Antenna subsystem for COMS(Communications, Ocean, and Meteorological Satellite) which will be launched at the end of 2008. The antenna subsystem employs the two parts: East Panel and West panel of spacecraft. ETRI in cooperation with domestic companies are under design phase for the antenna subsystem development. This paper focuses in the Ka-band reflector pointing error analysis to verify the antenna subsystem performance specification, especially EOC gain variation etc. The analysis performed is that induced by reflector surface deformation as a result of thermo elastic distortion. Beam pattern variations are verified by the use TICRA

• Journal of Broadcast Engineering
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• v.14 no.3
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• pp.271-279
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• 2009

The Moving Picture Experts Group (MPEG) and Video Coding Experts Group (VCEG) have developed a new standard that promises to outperform the earlier MPEG-4 and H.263 standards. The new standard is called H.264/AVC (Advanced Video Coding) and is published jointly as MPEG-4 Part 10 and ITU-T Recommendation H.264. In particular, the H.264/AVC intra prediction coding provides nine directional prediction modes for every $4{\times}4$ block in order to reduce spatial redundancies. In this paper, an ABS (Adaptive Bit Skip) mode is proposed. In order to achieve coding efficiency, the proposed method can remove the mode bits to represent the prediction mode by using the similarity of adjacent pixels. Experimental results show that the proposed method achieves the PSNR gain of about 0.2 dB in R-D curve and reduces the bit rates about 3.6% compared with H.264/AVC.

• Journal of KIISE:Computer Systems and Theory
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• v.33 no.1_2
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• pp.44-51
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• 2006

In this paper, we present a network-based integrated nesting system, that is adapted a current engineering concept. Generally, sheet cutting processes proceed in turn following an existing order In this study, however, the special characteristics of these processes were analyzed and the processes were redesigned with distributed design so that they could be operated in a client/server environment. Also, the necessary sheet material cutting processes, part CAD, nesting, part CAM, and NC post-processor capabilities, were implemented so that many workers could handle them all on the Web. Compared to existing commonly used systems, the developed system can provide integrated work environment for cutting automation, allow job collaboration between workers, and it has proved that it can shorten the standby time for work. By grafting computer system technologies to sheet material cutting automation field, this research expects to contribute to the enhancement of factory automation efficiency and productivity.

• Journal of Navigation and Port Research
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• v.40 no.4
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• pp.189-196
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• 2016

We propose a virtual sailor training platform which supports emergency drills for ship's fire in virtual environment. Proposed platform not only enhances training efficiency by providing immersiveness, but also enables a consolidated virtual training due to the network-based multiplayer capabilities. Based on the offline fire simulation results using FDS and CFAST the platform visualizes a realistic fire spread in real-time. The training platform on the basis of the fire training material of the maritime safety education institute induces equipment proficiency and environment adaptation throughout immersive virtual environment in addition to procedure proficiency as well. In the implementation we showed that the equipment and environment controls and telepresence improve the training proficiency and enable collaborative virtual training that participates multiple trainees and induces cooperation for a common goal. Implementation of the platform demonstrated the skill mastery capability of the drill such as efficient fire apparatus controls and passenger controls.