• 제목/요약/키워드: research and development's output

검색결과 292건 처리시간 0.037초

태양광 인버터의 한국형 전력변환 효율에 관한 연구 (A Study of Korean Efficiency of PV PCS)

  • 김정환;유병규;소정훈;이기옥;유권종
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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    • pp.356-360
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    • 2009
  • Recent global environmental pollution and contamination and depletion of limited fossil energy prices surge as an energy source to replace it depending on wind, fuel cells and solar power and other renewable and pollution free renewable energy is of interest in increase. The photovoltaic systems are pollution-free, unlimited energy source, and easy to install because it is rated as the most valuable renewable energy sector and the prevalence is spreading throughout the world. Photovoltaic systems at one end of the stable development of the role that solar power inverter applications can be the most important. No matter how much power the solar arrays, even if the inverter output in the normally if he's no use. These photovoltaic inverters to evaluate the performance of the inverter efficiency measures that can be called directly. This way of measuring the efficiency of solar inverters in Europe efficiency and CEC efficiency is currently being used. In this paper, until now about how to measure the efficiency of solar power inverter technology and the new Korean Meteorological Solar Insolation data analysis to derive weights based on this inverter efficiency for Korea is to offer.

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해양레저이벤트의 경제적 파급효과 분석 (Analyses of Economic Impacts of an Marine Leisure Event on the Host City)

  • 조우정;강신범
    • 한국항해항만학회지
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    • 제35권5호
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    • pp.415-421
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    • 2011
  • 본 연구는 최근 많은 지방자치단체의 관심을 끌고 있는 해양레저이벤트의 경제적 파급효과를 분석하기 위해 B광역시에서 개최한 국제 해양레저이벤트 방문객 및 선수단에 대한 소비지출 현황조사와 이벤트개최도시의 투자지출 자료를 활용해 해양레저이벤트의 산업연관분석을 실시해 다음과 같은 결론을 도출하였다. 첫째, 해양레저이벤트의 방문객 및 선수단의 소비지출에 따른 직접효과는 3.87억원이었으며 이에 따른 생산유발효과는 5.91억원, 부가가치유발효과는 3.06억원 그리고 소득유발효과는 2.52억원이었다. 둘째, 해양레저이벤트 개최도시의 투자지출에 따른 경제적 파급효과는 생산유발효과는 8.25억원, 부가가치유발효과는 4.32억원 그리고 소득유발효과는 3.66억원이었다. 결론적으로 본 연구는 해양레저이벤트 개최의 파급효과을 극대화하기 위한 마케팅 전략 및 정책 수립의 기초자료를 제공하고 있다.

Constructing an Internet of things wetland monitoring device and a real-time wetland monitoring system

  • Chaewon Kang;Kyungik Gil
    • Membrane and Water Treatment
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    • 제14권4호
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    • pp.155-162
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    • 2023
  • Global climate change and urbanization have various demerits, such as water pollution, flood damage, and deterioration of water circulation. Thus, attention is drawn to Nature-based Solution (NbS) that solve environmental problems in ways that imitate nature. Among the NbS, urban wetlands are facilities that perform functions, such as removing pollutants from a city, improving water circulation, and providing ecological habitats, by strengthening original natural wetland pillars. Frequent monitoring and maintenance are essential for urban wetlands to maintain their performance; therefore, there is a need to apply the Internet of Things (IoT) technology to wetland monitoring. Therefore, in this study, we attempted to develop a real-time wetland monitoring device and interface. Temperature, water temperature, humidity, soil humidity, PM1, PM2.5, and PM10 were measured, and the measurements were taken at 10-minute intervals for three days in both indoor and wetland. Sensors suitable for conditions that needed to be measured and an Arduino MEGA 2560 were connected to enable sensing, and communication modules were connected to transmit data to real-time databases. The transmitted data were displayed on a developed web page. The data measured to verify the monitoring device were compared with data from the Korea meteorological administration and the Korea environment corporation, and the output and upward or downward trend were similar. Moreover, findings from a related patent search indicated that there are a minimal number of instances where information and communication technology (ICT) has been applied in wetland contexts. Hence, it is essential to consider further research, development, and implementation of ICT to address this gap. The results of this study could be the basis for time-series data analysis research using automation, machine learning, or deep learning in urban wetland maintenance.

Fuzzy-Neuro Controller for Speed of Slip Energy Recovery and Active Power Filter Compensator

  • Tunyasrirut, S.;Ngamwiwit, J.;Furuya, T.;Yamamoto, Y.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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    • pp.480-480
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    • 2000
  • In this paper, we proposed a fuzzy-neuro controller to control the speed of wound rotor induction motor with slip energy recovery. The speed is limited at some range of sub-synchronous speed of the rotating magnetic field. Control speed by adjusting resistance value in the rotor circuit that occurs the efficiency of power are reduced, because of the slip energy is lost when it passes through the rotor resistance. The control system is designed to maintain efficiency of motor. Recently, the emergence of artificial neural networks has made it conductive to integrate fuzzy controllers and neural models for the development of fuzzy control systems, Fuzzy-neuro controller has been designed by integrating two neural network models with a basic fuzzy logic controller. Using the back propagation algorithm, the first neural network is trained as a plant emulator and the second neural network is used as a compensator for the basic fuzzy controller to improve its performance on-line. The function of the neural network plant emulator is to provide the correct error signal at the output of the neural fuzzy compensator without the need for any mathematical modeling of the plant. The difficulty of fine-tuning the scale factors and formulating the correct control rules in a basic fuzzy controller may be reduced using the proposed scheme. The scheme is applied to the control speed of a wound rotor induction motor process. The control system is designed to maintain efficiency of motor and compensate power factor of system. That is: the proposed controller gives the controlled system by keeping the speed constant and the good transient response without overshoot can be obtained.

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1018 nm 파장의 고출력 Yb 광섬유 레이저 (High-power Operation of a Yb Fiber Laser at 1018 nm)

  • 오예진;박혜미;박종선;박은지;김진필;정훈;김지원;김태형;정성묵;김기혁;양환석
    • 한국광학회지
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    • 제32권5호
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    • pp.209-214
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    • 2021
  • 본 논문에서는 단파장 영역인 1018 nm에서 최고 출력 626 W를 가진 고출력 이터븀(ytterbium, Yb) 첨가 광섬유 레이저에 대해 보고한다. Yb 광섬유 레이저에서 이득률이 낮은 단파장 영역인 1018 nm에서 레이저를 발진시키기 위한 조건을 이론적으로 조사해보고, 광섬유 끝 단단면 조건에 따른 되먹임 신호를 측정하여 안정적인 레이저 발진 조건에 대하여 연구하였다. 그 결과를 바탕으로 제작한 단일 공진기 구조의 Yb 광섬유 레이저 시스템으로부터 729 W의 펌프 출력에서 최고 출력 626 W의 1018 nm 파장 레이저 출력을 안정적으로 얻을 수 있었으며 그때 기울기 효율은 86.6%로 측정되었다. 본 연구에서 얻은 1018 nm 파장의 Yb 광섬유 레이저 결과는 지금까지 국내에서 보고된 1030 nm 이하 단파장에서 발진된 Yb 광섬유 레이저 출력 중 가장 높은 출력이며, 세계적으로도 상용 Yb 광섬유와 광부품을 사용한 결과 중 가장 높은 출력에 해당된다. 그리고 향후 더 높은 출력을 얻기 위한 방법에 대해 논의하고자 한다.

산림분야 기후변화대응 R&D사업에 대한 탐색적 성과분석 : 효율성 관점에서 DEA분석을 중심으로 (An Exploratory Performance Analysis of The Forest Sector R&D Program)

  • 문관식;임채홍;안경섭
    • 디지털융복합연구
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    • 제14권8호
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    • pp.47-56
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    • 2016
  • 본 연구는 산림분야 기후변화대응 R&D 사업을 통해 발생된 성과를 효율성 관점에서 분석하였다. 이를 위해 DEA(자료포락분석)를 활용하여 R&D 투자효과를 실증적으로 분석하였으며, 연구개발비와 인력 등의 투입(input)에 따라서 발생하는 과학적, 기술적, 사회적 성과의 산출(output) 및 결과(outcome)의 효율적 메카니즘을 규명하고, 세부 사업에서 어떠한 성과가 더 효율적으로 산출되는지를 심층적으로 분석하였다. Post-2012 온실가스 의무 감축 대응 산림정책 및 전략에 관한 연구과제가 과학적, 기술적, 사회적 성과에서 가장 참조 횟수가 많은 과제로 분석되어 가장 효율적인 것을 확인하였다. 이를 토대로 향후 R&D사업 추진의 핵심적 고려요소를 파악하고, 투자효과를 높일 수 있는 정책적인 시사점을 모색하였다.

3차원 CAD 시스템을 이용한 설계환경 구축 및 설계자동화에 대한 연구 (A Study on Construction of Design Environment and Design Automation Using 3D CAD System)

  • 김영일;전차수
    • 한국CDE학회논문집
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    • 제13권2호
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    • pp.139-152
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    • 2008
  • In order to survive worldwide competition, today's industries are experiencing strong pressure to introduce higher quality products with lower cost and shorter lead-time. Therefore, the role of design in the process of product development is increasing in significance. In this research, two methods for improving the design capability are proposed: construction of design environment and design automation using 3D CAD system. The designers and design process are the core of product design using 3D CAD system. In order to maximize the design performance, construction of the design environment including selection of a suitable system, designer training for best use of the system, establishment of an efficient design process, and stabilization of the environment are required. A method is suggested to construct design environment by systematizing the contents of the projects and consulting experiences carried out for various categories of business such as electronic devices, motorcycles, electricity parts, sanitary wares, injection molds, and die casing molds. Design automation helps reduce tedious and time-consuming jobs, simplify complicated and error-prone modeling and drawing works to shorten the lead time and improve the product quality. To develop a design automation system, understanding the process and the related knowledge on design are very important before implementing the system using API provided by 3D CAD system. In this research, an eight-step procedure is proposed for the development of a design automation system. These eight steps are analysis of needs, determination of specification, verification of specification using 3D CAD system, inspection of related API functions, programming, field test, application in practice, and maintenance. A case study in which five design automation systems in the design of turbine generators using the proposed method is introduced in detail. These systems play important roles in the generation of various output items including 3D models, drafts, material information, and NC data. The case study shows how effectively the design time is reduced and the quality improved using those systems.

MODFLOW or FEFLOW: A Case Study of Groundwater Model Selection for the Upper Waikato Catchment, New Zealand

  • Weir, Julian;Moore, Dr Catherine;Hadfield, John
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2011년도 학술발표회
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    • pp.14-14
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    • 2011
  • Groundwater in the Waikatoregion is a valuable resource for agriculture, water supply, forestry and industries. The 434,000 ha study area comprises the upper Waikato River catchment from the outflow of Lake Taupo (New Zealand's largest lake) through to Lake Karapiro (a man-made hydro lake with high recreational value) (Figure 1). Water quality in the area is naturally high. However, there are indications that this quality is deteriorating as a result of land use intensification and deforestation. Compounding this concern for decision makers is the lag time between land use changes and the realisation of effects on groundwater and surface water quality. It is expected that the effects of land use changes have not yet fully manifested, and additional intensification may take decadesto fully develop, further compounding the deterioration. Consequently, Environment Waikato (EW) have proposed a programme of work to develop a groundwater model to assist managing water quality and appropriate policy development within the catchment. One of the most important and critical decisions of any modelling exercise is the choice of the modelling platform to be used. It must not inhibit future decision making and scenario exploration and needs to allow as accurate representation of reality as feasible. With this in mind, EW requested that two modelling platforms, MODFLOW/MT3DMS and FEFLOW, be assessed for their ability to deliver the long-term modelling objectives for this project. The two platforms were compared alongside various selection criteria including complexity of model set-up and development, computational burden, ease and accuracy of representing surface water-groundwater interactions, precision in predictive scenarios and ease with which the model input and output files could be interrogated. This latter criteria is essential for the thorough assessment of predictive uncertainty with third-party software, such as PEST. This paper will focus on the attributes of each modelling platform and the comparison of the two approaches against the key criteria in the selection process. Primarily due to the ease of handling and developing input files and interrogating output files, MODFLOW/MT3DMS was selected as the preferred platform. Other advantages and disadvantages of the two modelling platforms were somewhat balanced. A preliminary regional groundwater numerical model of the study area was subsequently constructed. The model simulates steady state groundwater and surface water flows using MODFLOW and transient contaminant transport with MT3DMS, focussing on nitrate nitrogen (as a conservative solute). Geological information for this project was provided by GNS Science. Professional peer review was completed by Dr. Vince Bidwell (of Lincoln Environmental).

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Present status and prospect for development of mushrooms in Korea

  • Jang, Kab-Yeul;Oh, Youn-Lee;Oh, Minji;Im, Ji-Hoon;Lee, Seul-Ki;Kong, Won-Sik
    • 한국균학회소식:학술대회논문집
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    • 한국균학회 2018년도 춘계학술대회 및 임시총회
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    • pp.27-27
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    • 2018
  • The production scale of mushroom cultivation in Korea is approximately 600 billion won, which is 1.6% of the Korean gross agricultural output. Annually, ca. 190,000 tons of mushrooms are harvested in Korea. Although the numbers of mushroom farms and cultivators are constantly decreasing, the total mushroom yields are increasing due to the large-scale cultivation facilities and automation. The recent expansion of the well-being trend causes increase in mushroom consumption in Korea: annual per capita consumption of mushroom was 3.9kg ('13) that is a little higher than European's average. Thus the exports of mushrooms, mainly Flammulina velutipes and Pleurotus ostreatus, have been increased since the middle of 2000s. Recently, however, it is slightly reduced. However, Vietnam, Hong Kong, the United States, the Netherlands and continued to export, and the country has increased recently been exported to Australia, Canada, Southeast Asia and so on. Canned foods of Agaricus bisporus was the first exports of the Korean mushroom industry. This business has reached the peak of the sale in 1977-1978. As Korea initiated trade with China in 1980, the international prices of mushrooms were sharply fall that led to shrink the domestic markets. According to the high demand to develop new items to substitute for A. bisporus, oyster mushroom (Pleurotus ostreatus) was received the attention since it seems to suit the taste of Korean consumers. Although log cultivation technique was developed in the early 1970s for oyster mushroom, this method requires a great deal of labor. Thus we developed shelf cultivation technique which is easier to manage and allows the mass production. In this technique, the growing shelf is manly made from fermented rice straw, that is the unique P. ostreatus medium in the world, was used only in South Korea. After then, the use of cotton wastes as an additional material of medium, the productivity. Currently it is developing a standard cultivation techniques and environmental control system that can stably produce mushrooms throughout the year. The increase of oyster mushroom production may activate the domestic market and contribute to the industrial development. In addition, oyster mushroom production technology has a role in forming the basis of the development of bottle cultivation. Developed mushroom cultivation technology using bottles made possible the mass production. In particular, bottle cultivation method using a liquid spawn can be an opportunity to export the F.velutipes and P.eryngii. In addition, the white varieties of F.velutipes were second developed in the world after Japan. We also developed the new A.bisporus cultivar "Sae-ah" that is easy to grown in Korea. To lead the mushroom industry, we will continue to develop the cultivars with an international competitive power and to improve the cultivation techniques. Mushroom research in Korea nowadays focuses on analysis of mushroom genetics in combination with development of new mushroom varieties, mushroom physiology and cultivation. Further studied are environmental factors for cultivation, disease control, development and utilization of mushroom substrate resources, post-harvest management and improvement of marketable traits. Finally, the RDA manages the collection, classification, identification and preservation of mushroom resources. To keep up with the increasing application of biotechnology in agricultural research the genome project of various mushrooms and the draft of the genetic map has just been completed. A broad range of future studies based on this project is anticipated. The mushroom industry in Korea continually grows and its productivity rapidly increases through the development of new mushrooms cultivars and automated plastic bottle cultivation. Consumption of medicinal mushrooms like Ganoderma lucidum and Phellinus linteus is also increasing strongly. Recently, business of edible and medicinal mushrooms was suffering under over-production and problems in distribution. Fortunately, expansion of the mushroom export helped ease the negative effects for the mushroom industry.

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Topic Map을 활용한 연구개발정보의 연계 모델 개발 (Development of Cross Reference R&D Information Model using Topic Map)

  • 김재성;윤종민
    • 정보관리연구
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    • 제36권4호
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    • pp.155-174
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    • 2005
  • 최근 국가적 필요성의 인식 하에 과학기술정보, 특히 연구개발정보의 종합적 수집 관리 및 유통을 위한 국가 과학기술 종합정보 시스템(NTIS)의 개발이 논의되고 있다. 국가 과학기술 종합정보 시스템은 연구개발 프로세스, 연구개발활동, 연구개발정보, 연구개발 데이터 레벨의 구성요소들 간의 유기적 연계를 그 근간으로 한다. 본 논문에서는 국가 과학기술 종합정보 시스템의 개발에 기반이 되는 연구개발정보들 간의 상호연계 모델을 제안한다. 연계를 위해 고려되는 연구개발정보는 연구과제정보, 연구인력정보, 연구성과정보로 연구개발활동에 있어 매우 중요한 정보라 할 수 있다. 제안된 연계 모델을 통해 연구개발정보들 간의 상호 참조 및 탐색이 가능하며, 다양한 관점에서 다양한 형태의 질의를 수행할 수 있다. 연계 모델은 ISO13250 표준인 XML Topic Map을 이용하여 개발되었으며, 예제를 통해 연계 모델의 우수성 및 향후 활용가능성을 살펴보았다.