• Title/Summary/Keyword: D-효율

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High-efficiency PV Inverter using SiC (SiC 소자를 이용한 태양광 인버터의 효율 향상)

  • Lee, Jinmok;Oh, Seunghun;Koh, Kwang-soo;Kwon, Hyuuk-il;Park, Kyung-hun;Han, Kyung-sik
    • Proceedings of the KIPE Conference
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    • 2011.07a
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    • pp.302-303
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    • 2011
  • 일반적인 승압 컨버터와 H-bridge 인버터로 구성되는 비절연 계통연계형 태양광 인버터 시스템의 효율을 높이기 위해 H-bridge의 스위칭에 적합한 Unipolar 스위칭 방식을 선정하고, 또 SiC 다이오드를 사용함으로써 전체 효율을 향상시켰으며 이를 시뮬레이션과 실험으로 보여준다.

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PC1D Simulation for Optimization of Single Crystalline Silicon Solar Cell (PC1D를 이용한 단결정 실리콘 태양전지 효율의 최적화)

  • Lim, Won-Sub;Moon, In-Yong;Yi, Jun-Sin
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.57-58
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    • 2007
  • 결정질 실리콘 웨이퍼의 텍스쳐링과 도핑은 태양전지의 효율을 결정하는 매우 중요한 요인이다. 높은 효율을 갖는 태양전지 설계를 위해 PC1D를 이용하여 텍스쳐링 사면체의 폭 및 각도, 베이스 면저항 및 농도를 조절하였다. 최적화 결과, 텍스쳐 피라미드의 폭은 $2{\sim}4{\mu}m$, 각도는 $79^{\circ}$ 베이스 면저항 $100{\Omega}/{\Box}$, 도핑 농도 $1{\times}10^{19}cm^{-3}$에서 15.06%의 변환효율을 얻을 수 있다.

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A Study on NTIS Services for Efficient National R&D Management (효율적 연구관리를 위한 NTIS 서비스 분석)

  • Choi, Heeseok;Jung, Ocknam;Han, Heejun;Kim, Yunjeong;Kim, Jaesoo
    • Proceedings of the Korea Information Processing Society Conference
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    • 2013.05a
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    • pp.976-978
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    • 2013
  • 최근 국가R&D 효율성 제고를 위하여 연구관리 강화를 위한 노력들이 매우 중요하게 인식되고 있다. 국가과학기술지식정보서비스(NTIS)는 R&D 효율성 강화를 위한 국가R&D정보 지식 포털로 자리매김하고 있다. 본 연구에서는 한국의 NTIS와 일본 문부과학성이 운영하는 부처공동연구개발관리시스템(e-Rad)을 연구관리 측면에서 비교 분석하고, 특히 연구자 편의성을 제고하는 관점에서의 연구관리 효율화를 위해 범부처적으로 공동활용이 가능한 서비스 요소들을 도출한다. 이를 바탕으로 향후 NTIS 개선방향에 대한 시사점을 분석한다.

Texture video coding based on Occupancy information in V-PCC (V-PCC 를 위한 Occupancy 정보 기반의 Texture 영상 부호화 방법)

  • Gwon, Daehyeok;Choi, Haechul
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2021.06a
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    • pp.151-153
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    • 2021
  • 포인트 클라우드는 특정 개체 혹은 장면을 다수의 3 차원 포인터를 사용하여 표현하는 데이터의 표현 방식 중 하나로 3D 데이터를 정밀하게 수집하고 표현할 수 있는 방법이다. 하지만 방대한 양의 데이터를 필요로 하기 때문에 효율적인 압축이 필수적이다. 이에 따라 국제 표준화 단체인 Moving Picture Experts Group 에서는 포인트 클라우드 데이터의 효율적인 압축 방법 중 하나로 Video based Point Cloud Compression(V-PCC)에 대한 표준을 제정하였다. V-PCC 는 포인트 클라우드 정보를 Occupancy, Geometry, Texture 와 같은 다수의 2D 영상으로 변환하고 각 2D 영상을 전통적인 2D 비디오 코덱을 활용하여 압축하는 방법이다. 본 논문에서는 V-PCC 에서 변환하는 Occupancy 의 정보를 활용하여 효율적으로 Texture 영상을 압축할 수 있은 방법을 소개한다. 또한 제안방법이 V-PCC 에서 약 1%의 부호화 효율을 얻을 수 있음을 보인다.

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Coding Efficiency Improvement By Applying Rate-Distortion Optimization To 3D-DCT Based Integral Image Compression Method (3D-DCT 기반 집적영상 압축 방법의 율-왜곡 최적화를 통한 부호화 효율 향상 방법)

  • Jeon, Ju-Il;Kang, Hyun-Soo
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.1-8
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    • 2012
  • In this paper, we propose a rate-distortion optimization method to improve the coding efficiency of the conventional 3D-DCT based compression method using adaptive block mode selection for integral images. In the conventional 3D-DCT based compression method, 3D-DCT blocks of variable block sizes are adaptively selected depending on the characteristics of integral images, and then 3D-DCT is performed. The proposed method applies a rate-distortion optimization to determine the optimal block mode. In addition, we suggest the optimal Lagrangian parameter for integral images. Experimental results show that the proposed method gives bit-rate reduction of about 5%.

A Study on the Efficient Management Plan of Water Distribution Reservoirs Facility Using 3D Geospatial Information (3D 공간정보를 이용한 배수지시설물의 효율적인 관리방안에 관한 연구)

  • Jung, In Hun;Ro, Young Suk;Choi, Yun Soo;Woo, Sang Yoon;Kim, Chong Mun
    • Spatial Information Research
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    • v.20 no.6
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    • pp.109-118
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    • 2012
  • Recent increasement of metropolitan infrastructure due to rapid expansion and development of urban areas which caused complexity and diversification of management system demands higher cost and effort to manage and maintain the facilities. The reason why it requires continuous and systematic management by national government is that the infrastructure facilities takes important role as it is directly related to public's living. Thus this study suggests an efficient management plan for increasement of work efficiency, cost reduction, and time saving by introducing 3D geospatial information system for water distribution reservoirs which is managed by the Office of Waterworks Seoul Metropolitan Government. This study evaluates and quantifies the range of work improvement using the 3D GIS technology through carrying out a survey targeting people in charge of the Office of Waterworks Seoul Metropolitan Government and other 8 offices. From the result of the research, applying the 3D-GIS improves by 90.32%, 93.55%, and 91.61% in the area of work efficiency, cost reduction, and time saving respectively. Consequently, using 3D GIS in future management of infrastructure could be used as a way of producing base data which supports administrative decision making through statistical and case analysis based on continuous data management. Also it would contribute to improving work efficiency by improving management system through preventing data omission.

A Study on the Construction of the National R&D Knowledge Information -Mainly Focused on the Research Planning and Management- (국가 R&D 지식정보관리시스템 구축에 관한 연구 -연구기획 및 관리를 중심으로-)

  • You, Neom-Jeong;Choi, Ki-Seok
    • Journal of the Korean Society for Library and Information Science
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    • v.38 no.1
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    • pp.281-301
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    • 2004
  • The national investment versus research result management ratio is very low as we compare to those of other advanced countries. Also the system of efficient usage of research result is insufficient. It results inefficient R&D investment when we drive national R&D programs. In this paper we developed a generalized information system for efficient planning and management of national R&D programs. And we developed a efficient system of the R&D information support and a system of a smoothly circulating R&D information. Also we apply those systems to the development of the information system of Korea Research Council of Fundamental science and technology. This application system can provide a total R&D information of whole life cycle of the national R&D programs.

The Development of R&D SEA Measures in National R&D Programs Evaluation (국가연구개발사업의 성과평가를 위한 SEA 측정치 개발)

  • 이종식
    • Proceedings of the Technology Innovation Conference
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    • 1997.07a
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    • pp.247-265
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    • 1997
  • The objectives of not-for-profit organizations including government supported research institutes are, by definition, to achieve socially desired nonfinancial goals. Current reporting focuses on providing information to meet the needs of users. This information may be provided in the annual research report, financial report, and other reports. An objective of current reporting is to provide users with information that will assist them in evaluating the performance(efficiency and effectiveness) of reporting entity. The evaluation of R&D project's performance requires information not only about the acquition and use of resources, but also about the outputs and outcomes of R&D activities, This study aims to recommend that R&D Service Efforts and Accomplish- mints(SEA) reporting is useful for performance evaluation in national R&D programmes. To achieve this aims, I attempt to develop the R&D SEA measures with reference to the Concepts Statement No. 2 of the Governmental Accounting Standards Board. R&D SEA measures consist of five categories : (1) input measures, (2) outcome measures, (3) output measures, (4) re1a1e efforts to accomplishments, (5) explanatory information.

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Energy Efficient Data Transmission Algorithms in 2D and 3D Underwater Wireless Sensor Networks (2차원 및 3차원 수중 센서 네트워크에서 에너지 효율적인 데이터전송 알고리즘)

  • Kim, Sung-Un;Park, Seon-Yeong;Cheon, Hyun-Soo;Kim, Kun-Ho
    • Journal of Korea Multimedia Society
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    • v.13 no.11
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    • pp.1657-1666
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    • 2010
  • Underwater wireless sensor networks (UWSN) need stable efficient data transmission methods because of environmental characteristics such as limited energy resource, limited communication bandwidth, variable propagation delay and so on. In this paper, we explain an enhanced hybrid transmission method that uses a hexagon tessellation with an ideal cell size in a two-dimensional underwater wireless sensor network model (2D) that consists of fixed position sensors on the bottom of the ocean. We also propose an energy efficient sensing and communication coverage method for effective data transmission in a three-dimensional underwater wireless sensor network model (3D) that equips anchored sensors on the bottom of the ocean. Our simulation results show that proposed methods are more energy efficient than the existing methods for each model.

Implementation of 3D Height Map Tool for SnowBoard Game (스노우보드 게임을 위한 3D Height Map Tool 구현)

  • Kim Eun-Ju
    • Proceedings of the Korea Information Processing Society Conference
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    • 2006.05a
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    • pp.177-180
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    • 2006
  • 체감형 게임을 하기 위한 지형 인터페이스 모델로써 스노우보드 게임에서 사용되는 지형 Map Tool을 구현한다. 게임에 쓰이게 될 3D 지형을 하이트 2D 맵 편직기만을 이용해서 만들기는 힘들며 이러한 방법은 지형의 세밀함이 떨어지고 게임상에서 계속 불러들여 확인하는 것은 비효율적이다. 하이트맵을 3D 상에서 직접 불러와 편집을 하고 저장할 수 있게 된다면 훨씬 효율적이며 퀄리티를 높일 수 있을 것이다.

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