• Title/Summary/Keyword: Boundary linking

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Automatic Moving Object Segmentation using Robust Edge Linking for Content-based Coding (내용 기반 코딩을 위한 강력한 에지 연결에 의한 움직임 객체 자동 분할)

  • 김준기;이호석
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.5_6
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    • pp.305-320
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    • 2004
  • Moving object segmentation is a fundamental function for content-based application. Moving object edges are produced by matching the detected moving edges with the current frame edges. But we can often experience the object edge disconnectedness due to coincidence of similarity between the object and background colors or the decrease of movement of moving object. The edge disconnectedness is a serious problem because it degrades the object visual quality so conspicuously That it sometimes makes it inadequate to perform content-based coding. We have solved this problem by developing a robust and comprehensive edge linking algorithm. And we also developed an automatic moving object segmentation algorithm. These algorithms can produce the completely linked moving object edge boundary and the accurate moving object segmentation. These algorithms can process CIF 30 frames/sec in a PC. These algorithms can be used for the MPEG-4 content-based coding.

Response of Ecosystem Carbon and Water Vapor Exchanges in Evolving Nocturnal Low-Level Jets

  • Hong, Jin-Kyu;Mathieu, Nathalie;Strachan, Ian B.;Pattey, Elizabeth;Leclerc, Monique Y.
    • Asian Journal of Atmospheric Environment
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    • v.6 no.3
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    • pp.222-233
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    • 2012
  • The nocturnal low-level jet makes a significant impact on carbon and water exchanges and turbulent mixing processes in the atmospheric boundary layer. This study reports a case study of nocturnal surface fluxes such as $CO_2$ and water vapor in the surface layer observed at a flat and homogeneous site in the presence of low-level jets (LLJs). In particular, it documents the temporal evolution of the overlying jets and the coincident response of surface fluxes. The present study highlights several factors linking the evolution of low-level jets to surface fluxes: 1) wavelet analysis shows that turbulent fluxes have similar time scales with temporal scale of LLJ evolution; 2) turbulent mixing is enhanced during the transition period of low-level jets; and 3) $CO_2$, water vapor and heat show dissimilarity from momentum during the period. We also found that LLJ activity is related not only to turbulent motions but also to the divergence of mean flow. An examination of scalar profiles and turbulence data reveal that LLJs transport $CO_2$ and water vapor by advection in the stable boundary layer, suggesting that surface fluxes obtained from the micrometeorological method such as nocturnal boundary layer budget technique should carefully interpreted in the presence of LLJs.

Electric Field Analysis of Power Cable Joint Point using Boundary Element Method (경계요소법을 이용한 전력케이블 접속부의 전계해석)

  • 조경순
    • Journal of the Korea Computer Industry Society
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    • v.4 no.4
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    • pp.579-588
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    • 2003
  • There are many unfavorable conditions that lead to shortening life of cable by causing dielectric breakdown and aging such as field concentrations occurring in intermediate materials linking each cables, penetration of various impurities, and undermining of cable insulation layers. This paper simulated investigated partial discharge properties of XLPE which is widely used for ultra high voltage cable insulation materials and EPDM which is being used as insulation layer of cable joint materials kit, using Boundary Element Method. The result of computer simulation showed that inner-Void defect caused silicone oil to weaken the E-field effect. and we also found that E-field distribution in EPDM remained relatively lower than that in XLPE.

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Two scale modeling of behaviors of granular structure: size effects and displacement fluctuations of discrete particle assembly

  • Chu, Xihua;Yu, Cun;Xiu, Chenxi;Xu, Yuanjie
    • Structural Engineering and Mechanics
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    • v.55 no.2
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    • pp.315-334
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    • 2015
  • This study's primary aim is to check the existence of a representative volume element for granular materials and determine the link between the properties (responses) of macro structures and the size of the discrete particle assembly used to represent a constitutive relation in a two-scale model. In our two-scale method the boundary value problem on the macro level was solved using finite element method, based on the Cosserat continuum; the macro stresses and modulus were obtained using a solution of discrete particle assemblies at certain element integration points. Meanwhile, discrete particle assemblies were solved using discrete element method under boundary conditions provided by the macro deformation. Our investigations focused largely on the size effects of the discrete particle assembly and the radius of the particle on macro properties, such as deformation stiffness, bearing capacity and the residual strength of the granular structure. According to the numerical results, we suggest fitting formulas linking the values of different macro properties (responses) and size of discrete particle assemblies. In addition, this study also concerns the configuration and displacement fluctuation of discrete particle assemblies on the micro level, accompanied with the evolution of bearing capacity and deformation on the macro level.

Line segment grouping method for building roof detection in aerial images (항공영상에서 건물지붕 검출을 위한 선소의 그룹화 기법)

  • Ye, Cheol-Su;Im, Yeong-Jae;Yang, Yeong-Gyu
    • 한국지형공간정보학회:학술대회논문집
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    • 2002.11a
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    • pp.133-140
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    • 2002
  • This paper presents a method for line segment grouping used for detection of various building roofs. First, by using edge preserving filtering. noise is eliminated and then images are segmented by watershed algorithm, which preserves location of edge pixels. To extract line segments between control points from boundary of each region, we calculate curvature of each pixel on the boundary and then find the control points. Line linking is performed according to direction and length of line segments and finally the location of line segments is adjusted using gradient magnitudes of all pixels of the line segment. The algorithm has been applied to aerial imagery and the results show accurate building roof detection.

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A Study on the Application Plan of the Cadastral Resurvey in South Korea Through a Case Analysis of the Japanese Private-Public Boundary (일본 관민경계 사례분석을 통한 우리나라 지적재조사 적용방안에 관한 연구)

  • KIM, Jae-Myeong;LEE, Dong-Hwa
    • Journal of the Korean Association of Geographic Information Studies
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    • v.22 no.1
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    • pp.39-50
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    • 2019
  • Since the "Special Law on Cadastral Resurvey" was enforced in 2012, the Cadastral Resurvey Project in South Korea has been promoted in earnest. However, it has been difficult to obtain the following items: a budget for the project, the establishment of land boundaries by increasing/decreasing the area of the parcels of land in the downtown area, the calculation of the adjustment fee, and the analysis of the relationship between the business owner and the landowner in regards to conflicts of opinion. The analysis of Japan's private-public boundary system, which is promoting the Cadastral Resurvey ahead of South Korea, should not attempt to determine complex interests, especially when they are pursuing consensus of the boundary setting portion of the Cadastral Resurvey Project. Therefore, this study shows that there is a need to reduce the number of stakeholders and promote them by using a step-by-step process. The introduction of cost-saving measures for the Cadastral Resurvey through a private-public boundary preliminary investigation is needed. This study suggested the following: link the precision road map construction business using MMS, introduce the preliminary research projects for the Cadastral Resurvey, and gather the important land survey information for the private-public boundary basic survey. In order to establish the utilization base, the researcher proposed linking the downtown area regeneration with the downtown area planning business.

Analysis of Chemically and Thermally Induced Residual Stresses in Polymeric Thin Film

  • Lee, Sang Soon
    • Journal of the Semiconductor & Display Technology
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    • v.14 no.1
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    • pp.1-5
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    • 2015
  • This paper deals with the residual stresses developed in an epoxy film deposited on Si wafer. First, chemically induced residual stresses due to the volumetric shrinkage in cross-linking resins during polymerization are treated. The curvature measurement method is employed to investigate the residual stresses. Then, thermally induced stresses are investigated along the interface between the epoxy film and Si wafer. The boundary element method is employed to investigate the whole stresses in the film. The singular stress is observed near the interface corner. Such residual stresses are large enough to initiate interface delamination to relieve the residual stresses.

LIMIT RELATIVE CATEGORY THEORY APPLIED TO THE CRITICAL POINT THEORY

  • Jung, Tack-Sun;Choi, Q-Heung
    • Bulletin of the Korean Mathematical Society
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    • v.46 no.2
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    • pp.311-319
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    • 2009
  • Let H be a Hilbert space which is the direct sum of five closed subspaces $X_0,\;X_1,\;X_2,\;X_3$ and $X_4$ with $X_1,\;X_2,\;X_3$ of finite dimension. Let J be a $C^{1,1}$ functional defined on H with J(0) = 0. We show the existence of at least four nontrivial critical points when the sublevels of J (the torus with three holes and sphere) link and the functional J satisfies sup-inf variational inequality on the linking subspaces, and the functional J satisfies $(P.S.)^*_c$ condition and $f|X_0{\otimes}X_4$ has no critical point with level c. For the proof of main theorem we use the nonsmooth version of the classical deformation lemma and the limit relative category theory.

The Roughing Tool-Path Generation of Die-Cavity Shape Using the Drill (Drill을 이용한 Die-Cavity 형상의 황삭 가공 경로 생성)

  • Lim, P.;Lee, H. G;Yang, G. E.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2001.04a
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    • pp.398-401
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    • 2001
  • This paper presents rough cutting pat고 drilling. This method has differences from conventional method which uses boundary curve by intersecting object to machine and each cutting plane. Die-cavity shape is drilled in z-map, we select various tool and remove much material in the short time. as a result, this method raise productivity. The major challenges in die-cavity pocketing include : 1)finding an inscribed circle for removing material of unmachined regions, 2) selecting optimal tool and efficiently arranging tool, 3) generating offset surface of shape, 4) determining machined width according to the selected tool, 5) detecting and removing unmachined regions, and 6) linking PJE(path-joining element). Conventional machining method calling contour-map is compared with drilling method using Z-map, for finding efficiency in the view of productivity.

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The Effect of the Chemical Lateral Boundary Conditions on CMAQ Simulations of Tropospheric Ozone for East Asia (동아시아지역의 CMAQ 대류권 오존 모의에 화학적 측면 경계조건이 미치는 효과)

  • Hong, Sung-Chul;Lee, Jae-Bum;Choi, Jin-Young;Moon, Kyung-Jung;Lee, Hyun-Ju;Hong, You-Deog;Lee, Suk-Jo;Song, Chang-Keun
    • Journal of Korean Society for Atmospheric Environment
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    • v.28 no.5
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    • pp.581-594
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    • 2012
  • The goal of this study is to investigate the effects of the chemical lateral boundary conditions (CLBCs) on Community Multi-scale Air Quality (CMAQ) simulations of tropospheric ozone for East Asia. We developed linking tool to produce CLBCs of CMAQ from Goddard Earth Observing System-Chemistry (GEOS-Chem) as a global chemistry model. We examined two CLBCs: the fixed CLBC in CMAQ (CLBC-CMAQ) and the CLBC from GEOS-Chem (CLBC-GEOS). The ozone fields by CMAQ simulation with these two CLBCs were compared to Tropospheric Emission Spectrometer (TES) satellite data, ozonesonde and surface measurements for May and August in 2008. The results with CLBC-GOES showed a better tropospheric ozone prediction than that with CLBC-CMAQ. The CLBC-GEOS simulation led to the increase in tropospheric ozone concentrations throughout the model domain, due to be influenced high ozone concentrations of upper troposphere and near inflow western and northern boundaries. Statistical evaluations also showed that the CLBC-GEOS case had better results of both the index of Agreement (IOA) and mean normalized bias. In the case of IOA, the CLBC-GEOS simulation was improved about 0.3 compared to CLBC-CMAQ due to the better predictions for high ozone concentrations in upper troposphere.