• 한국태양에너지학회 논문집
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• 제30권2호
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• pp.81-86
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• 2010

Since the solar energy resource is the main input for sizing any solar photovoltaic system and solar thermal power system, it is essential to utilize the solar radiation data as a application and development of solar energy system increase. It will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 and direct normal insolation data since December 1992 at 16 different locations in Korea. Because of a poor reliability of existing data, KIER's new data will be extensively used by solar energy system users as well as by research institutes. From the results, the yearly averaged horizontal global insolation was turned out 3.60kWh/$m^2$/day and a significant difference of horizontal global insolation is observed between 1982~1990 and 1991~1999, 2000~2008 through 16 different cities in Korea.

• 디지털산업정보학회논문지
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• 제19권3호
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• pp.233-244
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• 2023

Although artificial intelligence and machine learning technologies have been used in various fields, problems with personal information protection have arisen based on centralized data collection and processing. Federated learning has been proposed to solve this problem. Federated learning is a process in which clients who own data in a distributed data environment learn a model using their own data and collectively create an artificial intelligence model by centrally collecting learning results. Unlike the centralized method, Federated learning has the advantage of not having to send the client's data to the central server. In this paper, we quantitatively present the performance improvement when federated learning is applied using the building change detection learning data. As a result, it has been confirmed that the performance when federated learning was applied was about 29% higher on average than the performance when it was not applied. As a future work, we plan to propose a method that can effectively reduce the number of federated learning rounds to improve the convergence time of federated learning.

• 대한약리학회지
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• 제26권2호
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• pp.161-166
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• 1990

Kallikrein-kinin계는 신장의 혈류역학과 수분 및 전해질 배설의 조절자로서 역할을 하는 것으로 알려져 있다. Kallikrein-kinin계의 유효한 펩타이드중 하나인 bradykinin(BK)을 신동맥에 주입시 전해질 배설이 증가하는데 이 작용이 신혈류역학적 변동에 기인하는지 또는 신세뇨관의 전해질 운반에 대한 직접적인 작용에 기인하는지 아직 확실치 않다. 따라서 본 연구에서는 원위세뇨관(DT)과 피질집합관(CCT)에서의 전해질운반 의존성 산소소비에 대한 BK의 영향을 관찰하였다. BK$(0.1\;{\mu}M)$은 DT과 CCT의 산소소비를 유의하게 감소시켰으며 이 작용은 Na부재시 나타나지 않았고 ouabain전처치에 의해 차단되었다. 또한 이 작용은 mepacrine에 의해 유의하게 차단되었으며 indomethacin에 의하여는 차단되지 않았다. 이상의 결과는 BK이 DT과 CCT에서 Na운반과 관련한 산소소비를 억제시키며 이 작용에는 prostaglandin들이 관여하고 있지 않음을 시사한다.

• Tribology and Lubricants
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• 제25권6호
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• pp.387-398
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• 2009

The operation condition of recently designed pistons for high power and high speed diesel engine become more severe due to the increment of combustion pressure and temperature. So, in order to overcome high temperature, the application of the mono-metal cast aluminum alloy piston featuring an enclosed cast-in open cooling gallery has increased. In this research, it is developed a PCJ (piston cooling jet) rig tester, described the test procedure and validated the performance of sample piston cooling gallery design. Then the test rig will be used for developing the design technology of piston cooling gallery. The test rig is composed with oil reservoir and pumping system, oil jet system, piston fixing and moving system, collecting oil measuring system, and data measuring and recording system. It will be measured collecting efficiencies under conditions of a few piston positions, oil jet pressures and oil viscosities for a piston cooling gallery. Furthermore, the PCJ rig tester will be used for the optimum design of the oil cooling gallery which being applied to increase the cooling efficiency of pistons in diesel engines satisfying the EURO V emission regulation and the more.

• 한국초등과학교육학회지:초등과학교육
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• 제23권4호
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• pp.305-317
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• 2004

The learning materials in elementary school science textbooks should include all kinds of materials being used by both teachers and students in the science teaching. The major purpose of this research is to analysis textbooks and teacher's guidebooks prepared for the science teaching of 3-6 grade students. To clarify this research, we listed whole of the learning materials of science teaching for each grade and counted numbers being used for whole of the lessons of science. And according to the characteristics and the methods of its preparation of materials, the types of learning materials can be divided into 10 categories such as teaching equipments for science, test materials, consumables, audio-visual aids, teaching equipments in general, collecting' recycling materials, field studies' collected data, breeding' cultivation materials, manufacture materials, and etc. At the result of this research, the 7th national science curriculum needs total 844 items of learning materials for science education. They could be separated into ten types of categories such as 159 items of teaching equipments for science, 65 items of test materials, 116 items of consumables, 198 items of audio-visual aids, 64 items teaching equipments in general, 31 items of collecting' recycling materials, 38 items of field studies (collecting) materials, 17 items of breeding-cultivation materials, 58 items of manufacturing materials, 105 items of other materials. And we found out that there were 332 items of materials for the 3rd grade, 303 items for the 4th grade, 324 items for the 5th grade, and 254 items for the 6th grade. The result of this research could be useful for classroom activities for science teaching.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.41-44
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• 2008

In this paper, major species of tree were discriminated in compartment by using LiDAR data and optic imagery. This is an important work in forest field. A current digital stock map has created the aerial photo and collecting survey data. Unlike high resolution imagery, LiDAR data is not influenced by topographic effects since it is an active sensory system. LiDAR system can measure three dimension information of individual tree. And the main methods of this study were to extract reliable the individual tree and analysis techniques to facilitate the used LiDAR data for calculating tree crown 2D parameter. We should estimate the forest inventory for calculating parameter. 2D parameter has need of area, perimeter, diameter, height, crown shape, etc. Eventually, major species of tree were determined the tree parameters, compared a digital stock map.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.413-416
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• 2009

Since the solar radiation is main input for sizing any solar photovoltaic system and solar thermal power system, it will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 and direct normal insolation data since December 1992 at 16 different locations. Because of a poor reliability of existing data, KIER's new data will be extensively used by solar energy system users as well as by research institutes. Among some significant results, the yearly averaged horizontal global insolation was turned out 3.61 kWh/$m^2$/day and the yearly mean 5.38 kWh/$m^2$/day of the direct normal insolation was evaluated for clear days.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2007년도 학술발표회 논문집
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• pp.1464-1468
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• 2007

The restoration project of Cheonggyecheon was conducted to creates the refreshing water-friendly environment in the downtown Seoul. It already have passed almost 2 years after restoration. This project changed environment of Cheonggyecheon dramatically, so historic hydrological data became useless. There are not so many hydrological data to manage and control this newly restored urban stream. The main purpose of this study is collecting and analysing the hydrological data of Cheonggyecheon. At first, we analysed the mechanism of Cheonggyecheon discharge using the sewage design maps and some GIS data. We also monitored the water levels and discharges of 5 main points of Cheonggyecheon. Rating curves of these 5 points were derived. There were 249 blocks of water gates which were located at both sides of bank. We also monitored the behaviors of these water gates. Through the these monitorings, some equations were derived to give useful information to the manager of Cheonggyecheon.

• 태양에너지
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• 제6권1호
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• pp.70-76
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• 1986

Since the solar radiation is the main input for sizing any solar system, it will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy and Resources (KIER) has began collecting horizontal insolation data since May, 1982 at 15 different locations. Because of a poor reliability of existing data, KIER's new data will be extensively used by the solar system users as well as by research institutes. Among some significant results, we obtained the good results more than we had expected, it is very encouraging that the mean value of Korea's solar radiation is increased by more than 30%.

• 한국태양에너지학회 논문집
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• 제29권4호
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• pp.15-21
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• 2009

Since the solar radiation is main input for sizing any solar photovoltaic system and solar thermal power system, it will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 and direct normal insolation data since December 1992 at 16 different locations. Because of a poor reliability of existing data, KIER's new data will be extensively used by solar energy system users as well as by research institutes. Among some significant results, the yearly averaged horizontal global insolation was turned out 3.60 kWh/$m^2$/day and the yearly mean 2.62 kWh/$m^2$/day of the direct normal insolation was evaluated for all days.