• Title/Summary/Keyword: Application accuracy

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Architecture of 2-D DCT processor adopting accuracy comensator (정확도 보상기를 적용한 2차원 이산 코사인 변환 프로세서의 구조)

  • 김견수;장순화;김재호;손경식
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.10
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    • pp.168-176
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    • 1996
  • This paper presetns a 2-D DCT architecture adopting accurac y compensator for reducing the hardware complexity and increasing processing speed in VL\ulcornerSI implementation. In the application fields such as moving pictures experts group (MPEG) and joint photographic experts group (JPEG), 2-D DCT processor must be implemented precisely enough to meet the accuracy specifications of the ITU-T H.261. Almost all of 2-D DCT processors have been implemented using many multiplications and accumulations of matrices and vectors. The number of multiplications and accumulations seriously influence on comlexity and speed of 20D DCT processor. In 2-D DCT with fixed-point calculations, the computation bit width must be sufficiently large for the above accuracy specifications. It makes the reduction of hardware complexity hard. This paper proposes the accuracy compensator which compensates the accuracy of the finite word length calculation. 2-D DCT processor with the proposed accuracy compensator shows fairly reduced hardware complexity and improved processing speed.

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Improvement of the Accuracy in Machining Deep Pocket by Up Milling (상향절삭에 의한 깊은 홈 가공시 정밀도 향상에 대한 연구)

  • Lee, Sang-Kyu;Ko, Sung-Lim
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.4 s.97
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    • pp.220-228
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    • 1999
  • The machining accuracy has been improved with the development of NC machine tools and cutting tools. However, it is difficult to obtain a high degree of accuracy when machining deep pocket with long end mill, since machining accuracy is mainly dependant on the stiffness of the cutting tool. To improve surface accuracy in machining deep pocket using end mill, the performance by down cut and up cut is compared theoretically and experimentally. To verify usefulness of up milling, various experiments were carried out. As a result, it is found that up milling produce more accurate surface than down milling in machining deep pocket. For effective application of up milling, various values in helix angle, number of teeth, radial depth of cut and axial depth of cut are applied in experiment.

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Establishing Required LOD and Positioning Accuracy for Indoor Spatial Information Applications in Public Administrative Works

  • Park, Junho;Lee, Jiyeong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.2
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    • pp.103-112
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    • 2017
  • Due to the large size and high complexity of modern buildings, the interest and the studies about indoor spatial information are increasing. Previous studies related to indoor spatial information were mostly about relevant technologies, and the application of indoor spatial information has been less studied. In the present study, the public administrative work areas where indoor spatial information may be applied were identified by using a modified delphi technique. And the indoor LOD (Level of Detail) and indoor positioning accuracy for indoor spatial information applications considering user requirements was established as standards for efficiently establishing and providing services. The required LOD and positioning accuracy for services was established by reestablishing indoor LOD and positioning accuracy and classifying services with reference to those. The indoor LOD was reestablished from LOD 0 to 4 by focusing on service utilization and general recognition, and the positioning accuracy was reestablished in three levels by considering the accuracy of the present positioning technology and service utilization status.

The Application of CFD for Ship Design (선박설계를 위한 계산유체역학의 활용)

  • Kim Wu-Joan;Van Suak-Ho
    • Journal of computational fluids engineering
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    • v.8 no.2
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    • pp.42-48
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    • 2003
  • The issues associated with the application of CFD for ship design are addressed. Doubtlessly at the moment, CFD tools are very useful in evaluating hull forms prior to traditional towing tank tests. However, time-consuming pre-processing is an obstacle in the daily application of CFD tools to improve hull forms. The accuracy of computational modeling without sacrificing the usability of CFD system is also to be assessed. The wave generation is still predicted by using potential panel methods, while velocity profiles entering into propeller plane is solved using turbulent flow solvers. The choice of turbulence model is a key to predict nominal wake distribution within acceptable accuracy. The experimental data for CFD validation are invaluable to improve physical and numerical modeling. Other applications of CFD for ship design than hull form improvement are also given. It is certain that CFD can be a cost-effective tool for the design of new and better ships.

The Application of GPS (Global Positioning System) Technology into Geotechnical Information System with better Accuracy (지반정보시스템 정밀도 향상을 위한 GPS 기술의 국내 적용 사례 연구)

  • 김정한;황덕호;전해영;박성민;기창돈;장윤섭;윤서연;박형동
    • Proceedings of the Korean Geotechical Society Conference
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    • 2000.03b
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    • pp.297-302
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    • 2000
  • This paper reports the application of GPS (Global Positioning System) technique into the geotechnical information system. Typical example of such application can be the database of logging data. Other examples can be found from the surveying for road work, excavation work, landslide mapping and image processing of slope face. This paper also reports the enhancement method of the accuracy. The results from this study confirms that GPS could be a powerful tool for the future geotechnical investigation works in Korea.

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The Wireless Internet DGPS location information output system development for the LBS (LBS를 위한 무선인터넷 DGPS 위치정보 출력 시스템 개발)

  • Kang Jun-Mook;Cho Sung-Ho;Lee Eun-Soo;Kim Jae-Myoung
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.111-118
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    • 2006
  • The LBS (Location Based Service) location information is the element which is important decides the application of form service, Recently the location accuracy with the method which applies the wireless Internet DGPS improved inside 1 meter Like this. application of the LBS which corresponds In the location accuracy which Improves accurate the Location Information output system development which is accurate stands is essential. In this study which it sees it used 1:5000 digital map MS visual 6.0 Active X controls of the country geography intelligence Personnel and it developed the location information output module of web browser base. The location information output system which is developed it will be able to secure the convenient characteristic of precision and visual program of the digital map simultaneously and the maximum anger of LBS application is expected.

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Plane Position Accuracy Analysis of Extracted Data from LiDAR (LiDAR 추출 자료의 평면위치 정확도 분석)

  • Yoon Hee-Cheon;Park Joung-Hyun;Lee Chang-Bok;Kang Joon-Mook
    • Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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    • 2006.04a
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    • pp.119-124
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    • 2006
  • The world which based on knowledge and information is changing significantly. In the various knowledge and information, the importance of GSIS has increased for efficient application and management of country. The Geomatics has made a change rapidly, observation methods have improved too. The existing acquisition of Geoinformation depend on aerial photogtaphs, but new technology Jike application of high resolution satellite images. SAR and LiDAR, is the fastest. especially, LiDAR surveying is most advanced active observation technology and Geoinfomtation is acquired by reflection of its laser pulse. In this study. the position accuracy of extracted building from LiDAR was evaluated by GPS surveying, then each data was made comparison between LiDAR's and GPS's data. After processing. the result of this study will be suggested basic data about application.

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The Application of CED for Ship Design (선박설계를 위한 계산유체역학의 활용에 대하여)

  • Kim Wu-Joan
    • Proceedings of the KSME Conference
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    • 2002.08a
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    • pp.5-8
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    • 2002
  • The issues associated with the application of CFD for ship design are addressed. It is quite certain that the CFD tools are very useful in evaluating hull forms a prior to traditional towing tank tests. However, the time-consuming pre-processing is an obstacle in the daily application of CFD tools to improve hull forms. The accuracy of computational modeling without sacrificing the usability of CFD system is also to be assessed. The wave generation is still predicted by using potential panel methods, while velocity profiles entering into propeller plane is solved using turbulent flow solvers. The choice of turbulence model is a key to predict nominal wake distribution within acceptable accuracy. The experimental data for CFD validation are invaluable to improve physical and numerical modeling. Other applications of CFD for ship design than hull form improvement are also given. It is certain that CFD can be a cost-effective tool for the design of new and better ships.

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Nobel Approaches of Intelligent Load Model for Transient Stability Analysis (과도안정도 해석을 위한 지능형 부하모델의 새로운 접근법)

  • Lee, Jong-Pil;Lim, Jae-Yoon;Ji, Pyeong-Shik
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.57 no.2
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    • pp.96-101
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    • 2008
  • The field of load modeling has attracted the attention since it plays an important role for improving the accuracy of stability analysis and power flow estimation. Also, load modeling is an essential factor in the simulation and evaluation of power system performance. However, conventional load modeling techniques have some limitations with respect to accuracy for nonlinear and composite loads. Thus, precision load modeling technique and reasonable application method is needed for more accurate power system analysis. In this paper, we develop an intelligent load modeling method based. on neural network and application techniques for power system. The proposed method makes it possible to effectively estimate the load model for nonlinear models as well as linear models. Reasonable application method is also proposed for stability analysis. To demonstrate the validity of the proposed method, various experiments are performed and their results are presented.

A Study on the Analysis of Application of Non-metric Camera to Accident Sites (비측량용 사진기를 이용한 사고현장 적용 해석에 관한 연구)

  • Yeu, Bock Mo;Kim, In Sup;Cho, Gi Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.11 no.4
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    • pp.121-131
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    • 1991
  • This study is about the analysis of the application of non-metric camera to accident sites and aims to present an efficient, an economical and an accurate method of processing accident sites. This was accomplished by observation and accuracy analysis of an experimental model. It can be concluded that by applying the 3-D coordinate system and the bundle adjustment with additional parameters to non-metric cameras, it is possible to achieve an accuracy level of positional values which is similar to that achieved by conventional control surveying and by metric cameras. It was also found that the accuracy of absolute coordinates approached towards the accuracy of metric cameras with the increase of the film size and with the increase of the focal length of the non-metric camera.

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