• 제목/요약/키워드: single point

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강재 열처리용 다점 열유속 측정 기술 개발 (Development of Multi-point Heat Flux Measurement for Steel Quenching)

  • 이정호;오동욱;도규형;김태훈
    • 열처리공학회지
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    • 제25권4호
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    • pp.181-189
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    • 2012
  • The demand on quantitative measurement of the heat flux is motivated in making higher-quality steel product through a water quenching process of plate mill. To improve a spatial degree of heat flux measurement, the multi-point heat flux measurement was carried out by a unique experimental technique that has a combination of the existing single-point heat flux gauge. The corresponding heat flux can be easily determined by Fourier's law in a conventional way. The multi-point heat flux gauge developed in this study can be applicable to measure the surface heat flux, the surface heat transfer coefficient during a water quenching applications of steelmaking process. The results exhibit different heat transfer regimes; such as single-phase forced convection, nucleate boiling, and film boiling, that are occurred in close proximity on the multi-point heat flux gauge quenched by water impinging jet.

On the natural frequencies and mode shapes of a uniform multi-span beam carrying multiple point masses

  • Lin, Hsien-Yuan;Tsai, Ying-Chien
    • Structural Engineering and Mechanics
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    • 제21권3호
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    • pp.351-367
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    • 2005
  • Multi-span beams carrying multiple point masses are widely used in engineering applications, but the literature for free vibration analysis of such structural systems is much less than that of single-span beams. The complexity of analytical expressions should be one of the main reasons for the last phenomenon. The purpose of this paper is to utilize the numerical assembly method (NAM) to determine the exact natural frequencies and mode shapes of a multi-span uniform beam carrying multiple point masses. First, the coefficient matrices for an intermediate pinned support, an intermediate point mass, left-end support and right-end support of a uniform beam are derived. Next, the overall coefficient matrix for the whole structural system is obtained using the numerical assembly technique of the finite element method. Finally, the natural frequencies and the associated mode shapes of the vibrating system are determined by equating the determinant of the last overall coefficient matrix to zero and substituting the corresponding values of integration constants into the related eigenfunctions respectively. The effects of in-span pinned supports and point masses on the free vibration characteristics of the beam are also studied.

접촉점에서의 국소 그래프 패턴에 의한 필기체 한글의 자소분리에 관한 연구 (A Study on the Phoneme Segmentation of Handwritten Korean Characters by Local Graph Patterns on Contacting Points)

  • 최필웅;이기영;구하성;고형화
    • 전자공학회논문지B
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    • 제30B권4호
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    • pp.1-10
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    • 1993
  • In this paper, a new method of phoneme segmentation of handwritten Korean characters using the local graph pattern is proposed. At first, thinning was performed before extracting features. End-point, inflexion-point, branch-point and cross-point were extracted as features. Using these features and the angular relations between these features, local graph pattern was made. When local graph pattern is made, the of strokes is investigated on contacting point. From this process, pattern is simplified as contacting pattern of the basic form and the contacting form we must take into account can be restricted within fixed region, 4therefore phoneme segmentation not influenced by characters form and any other contact in a single character is performed as matching this local graph pattern with base patterns searched ahead. This experiments with 540 characters have been conducted. From the result of this experiment, it is shown that phoneme segmentation is independent of characters form and other contact in a single character to obtain a correct segmentation rate of 95%, manages it efficiently to reduce the time spent in lock operation when the lock.

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2-D Robust Design Optimization on Unstructured Meshes

  • Lee Sang Wook;Kwon Oh Joon
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2003년도 The Fifth Asian Computational Fluid Dynamics Conference
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    • pp.240-242
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    • 2003
  • A method for performing two-dimensional lift-constraint drag minimization in inviscid compressible flows on unstructured meshes is developed. Sensitivities of objective function with respect to the design variables are efficiently obtained by using a continuous adjoint method. In addition, parallel algorithm is used in multi-point design optimization to enhance the computational efficiency. The characteristics of single-point and multi-point optimization are examined, and the comparison of these two method is presented.

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An Improved Global Maximum Power Point Tracking Scheme under Partial Shading Conditions

  • Kim, Rae-Young;Kim, Jun-Ho
    • Journal of international Conference on Electrical Machines and Systems
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    • 제2권1호
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    • pp.65-68
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    • 2013
  • A photovoltaic array exhibits several local and single global maximum power points under partial shading conditions. To track the global maximum power point precisely, a novel global maximum power point tracking scheme is proposed in this paper. In the proposed scheme, robustness of the tracking performance has been improved by enhancing searching profile. In addition, the paper addresses the tracking failure condition, and provides the experimental verification with several simulation and experimental results.

Some Common Fixed Point Theorems using Compatible Maps in Intuitionistic Fuzzy Metric Space

  • Park, Jong-Seo
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제11권2호
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    • pp.108-112
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    • 2011
  • Kaneko et a1.[4] etc many authors extended with multi-valued maps for the notion of compatible maps in complete metric space. Recently, O'Regan et a1.[5] presented fixed point and homotopy results for compatible single-valued maps on complete metric spaces. In this paper, we will establish some common fixed point theorems using compatible maps in intuitionistic fuzzy metric space.

3D BUILDING INFORMATION EXTRACTION FROM A SINGLE QUICKBIRD IMAGE

  • Kim, Hye-Jin;Han, Dong-Yeob;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.409-412
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    • 2006
  • Today's commercial high resolution satellite imagery such as IKONOS and QuickBird, offers the potential to extract useful spatial information for geographical database construction and GIS applications. Recognizing this potential use of high resolution satellite imagery, KARI is performing a project for developing Korea multipurpose satellite 3(KOMPSAT-3). Therefore, it is necessary to develop techniques for various GIS applications of KOMPSAT-3, using similar high resolution satellite imagery. As fundamental studies for this purpose, we focused on the extraction of 3D spatial information and the update of existing GIS data from QuickBird imagery. This paper examines the scheme for rectification of high resolution image, and suggests the convenient semi-automatic algorithm for extraction of 3D building information from a single image. The algorithm is based on triangular vector structure that consists of a building bottom point, its corresponding roof point and a shadow end point. The proposed method could increase the number of measurable building, and enhance the digitizing accuracy and the computation efficiency.

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서비스 중심의 국가 공간정보 플랫폼 연계 방안에 관한 연구 (A Study on the Construction of Service-oriented Connection Model among National GeoSpatial Information Platforms)

  • 김병선;안종욱;신동빈
    • Spatial Information Research
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    • 제22권2호
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    • pp.11-18
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    • 2014
  • 본 연구는 공간정보 서비스 중심의 국가 공간정보 플랫폼 연계 방안을 제시하는 것을 목적으로 한다. 이를 위해 공간정보 플랫폼 연계의 필요성에 대해 분석하고, 산 학 연 전문가를 대상으로 설문조사를 실시하여 국가 공간정보 플랫폼 연계에 대한 문제점을 파악하였다. 이를 토대로 효율적인 공간정보 서비스 제공을 위한 Single Point Access 플랫폼 연계 모델과 이를 구현하기 위한 기술과 정책 방안을 제시하였다. 이러한 연구 결과는 공간정보 중심의 플랫폼 정부 구현, 국가 공간정보 플랫폼 개발에 대한 정책 방향 수립 및 국가 정보화 계획에 활용될 수 있을 것이다.

Two Novel 3-D Zinc Compounds with Mixture Ligands of H3BTB and 4,4'-Bipy: Crystal Structures, Blue Fluorescence and Single Point Energy Calculation

  • Zhang, Xiu-Cheng;Xu, Ling;Liu, Wen-Guang;Liu, Bing
    • Bulletin of the Korean Chemical Society
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    • 제31권9호
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    • pp.2598-2602
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    • 2010
  • Two 3-D zinc framework compounds, $[Zn_6(BTB)_4(4,4'-bipy)_4(H_2O)_4]{\cdot}9H_2O$ (1) and $[Zn_3(BTB)_2(4,4'-bipy)_2(H_2O)_2]{\cdot}5H_2O$ (2) ($H_3BTB$ = 1,2,3-benzenetricarboxylic acid, 4,4'-bipy = 4,4'-bipyridine), are obtained from the diffusion method and hydrothermal reaction respectively. Though 1 and 2 has the same coordination geometries of zinc atoms and coordination mode of $BTB^{3-}$, their 2-D layers are different: mirror symmetric layers in 1; parallel ones in 2, further connecting by 4,4'-bipy into 3-D frameworks. The hydrothermal reaction of 2 results in a more stable 3-D framework than the one in 1, which is supported by the single point energy calculations. 1 and 2 show similar blue fluorescence at 417 nm, which can be assigned to LMCT.

단상 인버터를 이용한 새로운 태양광 에너지 변환 시스템 구현 (A New Solar Energy Conversion System Implemented Using Single Phase Inverter)

  • 김실근;홍순일
    • 조명전기설비학회논문지
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    • 제20권7호
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    • pp.74-80
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    • 2006
  • 본 논문은 새로운 태양광 에너지 변환 기술에 의한 연계형 단상 인버터 제어기술을 나타내었다. 최대전력 점 추적제어는 두 부스터 컨버터의 MOSFET 스위치 제어 발생회로에 기초하고 단상 인버터는 풀 브리지의 4개 IGBT 스위치에 의해 전류 추종제어 된다. PV 모듈의 발생전력 제어회로는 PV 모듈의 출력 전압, 전류 검출에 의해 최대전력 점 제어한다. 결국 PV 모듈 양단은 인버터 입력전압으로 낮은 리플 전압을 유지하고 출력은 증가한다. 제안한 태양광 인버터 시스템의 효과가 시뮬레이션과 실험을 통하여 입증되었다.