• Title/Summary/Keyword: Boundary line

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Feature Extraction of Off-line Handwritten Characters Based on Optical Neural Field (시각 신경계 반응 모델에 근거한 필기체 off-line 문자에서의 특징 추출)

  • Hong, Keong-Ho;Jeong, Eun-Hwa;Ahn, Byung-Chul
    • The Transactions of the Korea Information Processing Society
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    • v.6 no.12
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    • pp.3530-3538
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    • 1999
  • In this paper, we propose a novel method for feature extraction of off-line handwritten characters recognition based on human optical neural field model. The proposed feature extraction system divide into three parts ; 1) smoothing process, 2) removing boundaries(boundary lines), 3) extracting feature information. The proposed system first removes rough pixels which are easy to occur in handwritten characters. The system then extracts and removes the boundary information which have no influence on characters recognition. Finally, the feature information for off-line handwritten characters recognition is extracted. With PE2 Hangul database, we perform feature extraction experiments for off-line handwritten characters recognition. In the experiment results, the proposed system based on optical neural field shows that can extract the feature information of off-line handwritten characters including curve lines, circles, quadrangles and so on.

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The Legal Issue in the Recent South-North Korean Naval Engagement: An Appraisal on The North Korean Theory of the Sea Demarcation Line in the Western Sea. (남해사태: 남북한 해상경계에 관한 북측 주장의 법적문제)

  • 김영구
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.5 no.2
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    • pp.125-139
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    • 1999
  • Thanks to the fact that the 1953 Korea Armistice Agreement does not have any clear provisions on the sea demarcation line, the North Korea insists that the sea demarcation line in the Yellow Sea Area should not be the NLL designated by the Commander in Chief. UN Command, unilaterally, but the hypothetical extention of the Latitude Parallel from the end of the provincial boundary line between Whanghae-do and Kyongki-do In those unique situations at the end of the Korean War, the cease-fire line on the part of the western sea area, a logically indispensable element of the contents of an armistice agreement, however has formed and crystallized by the act of the UN Command designating the NLL. In implementing the South-North Korean Basic Relations Agreement, a fair and clear common consent on the sea demarcation line in the western sea area should be deliberated.

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A SIMPLE GRANULE MODEL AND ITS EFFECT ON SPECTRAL LINE ASYMMETRY

  • KIM YONGCHEOL
    • Journal of The Korean Astronomical Society
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    • v.31 no.2
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    • pp.77-87
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    • 1998
  • The accumulated knowledge of the influence of solar granulation on spectral lines, i.e. their asymmetry, provides a key to analyze stellar spectral line asymmetries. In this paper, a simple line synthesis using a simple 'model' of granulation was calculated. By adjusting the properties of the granule model, the observed imprints of convection on spectral lines can be reproduced. Since we depict convective flows using a continuous function rather than using a few components of flows (cf. Gray and Toner 1985, 1986; dravins 1990), we were able to identify which components of convection are important in line bisector shapes. The results of this study can be summarized as follows: Firstly, the intensity contrast (i.e. temperature fluctuation), and the area coverage of up- and down-flows are the two important factors which determine the line bisector shapes. Secondly, on the contrary to the assumption of other studies, the effect of horizontal flows is non-negligible. This exercise provides a qualitative understanding of the effect of convection on spectral lines. This knowledge serves as a guideline for understanding the characteristic difference in convection for stars on either side of the 'Granulation Boundary' (Gray 1982; Gray and Nagel 1989).

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Identification of the Rigid Body Properties using the Mass-line of F.R.F. in Free-boundary Condition (자유경계 조건에서의 질량선에 의한 강체특성 규명)

  • 안세진;정의봉;황대선
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.11b
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    • pp.745-749
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    • 2001
  • The rigid body properties of a structure may be estimated easily if the mass-line of the structure could be taken exactly. However, the exact mass-line cannot be obtained experimentally. In the past years, the modal analysis for which the structure is mounted on the flexible supporter is frequently used to acquire the mass-line. Unfortunately, it is difficult not only to mount the structure but also to decouple the coupled 6 dof mode. If the structure is pended by very long and flexible rope to act free, the rigid-body modes influenced by the rope will be eliminated and the improved mass-line will be obtained. In this paper, the method using the mass-line of F.R.F. for rigid body in free-condition is suggested. The robustness of the suggested method was tested and verified numerically. The experimental results also showed a good agreement with the true value.

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Frequency-Dependent Line Capacitance and Conductance Calculations of On-Chip Interconnects on Silicon Substrate Using Fourier cosine Series Approach

  • Ymeri, H.;Nauwelaers, B.;Vandenberghe, S.;Maex, K.;De Roest, D.;Stucchi, M.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.1 no.4
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    • pp.209-215
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    • 2001
  • In this paper a method for analysis and modelling of coplanar transmission interconnect lines that are placed on top of silicon-silicon oxide substrates is presented. The potential function is expressed by series expansions in terms of solutions of the Laplace equation for each homogeneous region of layered structure. The expansion coefficients of different series are related to each other and to potentials applied to the conductors via boundary conditions. In the plane of conductors, boundary conditions are satisfied at $N_d$ discrete points with $N_d$ being equal to the number of terms in the series expansions. The resulting system of inhomogeneous linear equations is solved by matrix inversion. No iterations are required. A discussion of the calculated line admittance parameters as functions of width of conductors, thickness of the layers, and frequency is given. The interconnect capacitance and conductance per unit length results are given and compared with those obtained using full wave solutions, and good agreement have been obtained in all the cases treated

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An Application of the Maximum Principle to Distributive Electrical Circuits (분포정수를 갖는 전기회로에 대한 최대원리의 응용)

  • Yang, Heung-Suk
    • 전기의세계
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    • v.18 no.6
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    • pp.9-22
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    • 1969
  • This thesis has suggested a method of applying the Maximum Principle of Pontryagin to the optimal control of distributive electrical networks. In general, electrical networks consist of branches, nodes, sources and loads. The effective values of steady state currents and voltages are independent of time but only expressed as the functions of position. Moreover, most of the node voltages and branch currents are not predetermined, that is, initially unknown, and their inherent loop characteristics satisfy only Kirchhoff's current and voltage laws. The Maximum Principle, however, needs the initial fixed values of all state variables for its standand way of application. In spite of this inconsistency this thesis has undertaken to suggest a new approach to the successful solution of the above mentioned networks by introducing scaling factors and a state variable change technique which transform the boundary-value unknown problem into the boundary-value partially fixed and partially free problem. For the examples of applying the method suggested, the control problems for minimizing copper quantity in a distribution line have been solved with voltage drop constraint imposed on. In the case of uniform load distribution it has been shown that the optimal wire diameter of the distribution line is reciprocally proportional to the root of distance. For the same load pattern as above the wire diameter giving the minimum copper loss in the distribution line has been shown to be reciprocally proportional to distance.

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Efficient Analysis of Couplings through Periodically Arranged Slots in a Radial Line Slot Antenna (RLSA 설계를 위한 주기적으로 배열된 슬롯을 통한 결합의 효율적인 해석)

  • 이중원;김용훈;박종국;남상욱
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.6
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    • pp.931-939
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    • 2001
  • The slot coupling characteristics was analysed in a radial-line slot antenna for its design. The previously proposed waveguide model with a periodic boundary condition on its narrow walls and periodically arranged slots on its wide wall was used. The magnetic field integral equation and two dyadic Green\`s functions for respective regions was derived and the method of moments was used. To maximize the efficiency of numerical analysis and to extract singularities, two different kinds of basis functions, the entire domain basis function and the sub-domain one, are used. In addition, the Ewald sum technique for the rectangular waveguide and the Shanks transform for the half space were used to accelerate the computation of the slowly convergent potential Green\`s functions. Simulation results expressed the effects of the various design parameters on the slot coupling.

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A building roof detection method using snake model in high resolution satellite imagery

  • Ye Chul-Soo;Lee Sun-Gu;Kim Yongseung;Paik Hongyul
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.241-244
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    • 2005
  • Many building detection methods mainly rely on line segments extracted from aerial or satellite imagery. Building detection methods based on line segments, however, are difficult to succeed in high resolution satellite imagery such as IKONOS imagery, for most buildings in IKONOS imagery have small size of roofs with low contrast between roof and background. In this paper, we propose an efficient method to extract line segments and group them at the same time. First, edge preserving filtering is applied to the imagery to remove the noise. Second, we segment the imagery by watershed method, which collects the pixels with similar intensities to obtain homogeneous region. The boundaries of homogeneous region are not completely coincident with roof boundaries due to low contrast in the vicinity of the roof boundaries. Finally, to resolve this problem, we set up snake model with segmented region boundaries as initial snake's positions. We used a greedy algorithm to fit a snake to roof boundary. Experimental results show our method can obtain more .correct roof boundary with small size and low contrast from IKONOS imagery. Snake algorithm, building roof detection, watershed segmentation, edge-preserving filtering

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An Efficient Triangulation Algorithm for Trimmed NURBS Surfaces (트림된 NURBS 곡면의 효율적인 삼각화 알고리즘)

  • 정재호;박준영
    • Korean Journal of Computational Design and Engineering
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    • v.5 no.2
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    • pp.144-154
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    • 2000
  • We propose an algorithm for obtaining a triangular approximation of a trimmed NLRBS surface. Triangular approximation is used in the pre-processing step of many applications such as RP(Rapid Prototyping), NC(Numerical Control) and FEA(Finite Element Analysis), etc. The algorithm minimizes the number of triangular elements within tolerance and generates a valid triangular mesh for STL file and NC tool path generation. In the algorithm, a subdivision method is used. Since a patch is a basic element of triangular mesh creation, boundary curves of a patch are divided into line segments and the division of curves is applied for the interior of the surface. That is, boundary curves are subdivided into line segments and two end points of each line segment are propagated to the interior of the surface. For the case of a trimmed surface, triangulation is carried out using a model space information. The algorithm is superior because the number of elements can be controlled as the curvature of the surface varies and it generates the triangular mesh in a trimmed region efficiently. To verify the efficiency, the algorithm was implemented and tested for several 3D objects bounded by NURBS surfaces.

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A Study on the Expression Methods of Space Perception by the Scene in the Exhibition Space (전시공간에서의 장면에 의한 공간지각 표현방법에 관한 연구)

  • Kim, Han-Na;Seo, Ji-Eun
    • Korean Institute of Interior Design Journal
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    • v.22 no.5
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    • pp.293-301
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    • 2013
  • The purpose of this study was to find the space perception by the scene and to analyze the characteristics in the exhibition space. The data for the analysis was collected through a questionnaire survey method. The questionnaire is composed of a scene selection on the panoramic photographs of the exhibition space. 'The 4 Rivers Cultural Center - The ARK' was selected as the subject of this survey. The results of the study are presented as follows : First, the space perception perceived imaged scenes rather than the specific elements of space. Second, the space perception was revealed through the 'Form', 'Materials', 'Light', 'Lighting', 'Furniture' and 'Media' of notable elements. Also that was perceived by forming 'Line', 'Surface' and 'Volume'. Particularly, the perception of 'Surface' was higher than 'Line' and 'Volume'. 'Surface' was perceived mostly through the 'Color'. The perception of 'Line' was positive to 'Boundary' or 'Continuous placement of the light'. In addition, the perception of 'Volume' was positive to 'The curve of the form', 'Transparent material', 'Three-dimensional elements'. Finally, The type of space perception was chosen as 'Extension', 'Center', 'Deep', 'Boundary' and 'Formative'. In this way, the results of this study will set a foundation for developing design methods to induce the space perception by the scene in the exhibition space.