• 제목/요약/키워드: corner problem

검색결과 121건 처리시간 0.023초

Corner outlier 제거를 위한 후처리 기법 (Post-Processing for Reducing Corner Outliers)

  • 홍윤표;전병우
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
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    • pp.11-14
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    • 2003
  • In block-based lossy video compression, severe quantization causes discontinuities along block boundaries so that annoying blocking artifacts are visible in decoded video imases. These blocking artifacts significantly decrease the subjective image quality. In order to reduce the blocking artifacts in decoded images, many algorithms have been proposed However studies on so called, corner outliers, have been very limited. Corner outliers make image edges look disconnected from those of neighboring blocks at cross block boundary. In order to solve this problem, we propose a corner outlier detection and compensation algorithm as post-processing in spatial domain The experiment results show that the proposed method provides much improved subjective image quality.

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크기와 회전변화에 강인한 Genetic Programming 기반 코너 검출자 (Scale and Rotation Robust Genetic Programming-Based Corner Detectors)

  • 서기성;김영균
    • 제어로봇시스템학회논문지
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    • 제16권4호
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    • pp.339-345
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    • 2010
  • This paper introduces GP(Genetic Programming) based robust corner detectors for scaled and rotated images. Various empirical algorithms have been studied to improve computational speed and accuracy including approaches, such as the Harris and SUSAN, FAST corner detectors. These techniques are highly efficient for well-defined corners, but are limited to corner-like edges which are often generated in rotated images. It is very difficult to detect correctly edges which have characteristics similar to corners. In this paper, we have focused the above challenging problem and proposed Genetic Programming-based automated generation of corner detectors which is robust to scaled and rotated images. The proposed method is compared to the existing corner detectors on test images and shows superior results.

한.중.일 목조 불탑의 비교론적 고찰(I) - 귀공포를 중심으로 - (A Comparative Study Wooden Stupa of Korea, Japan and China(I) - Focused on the Corner Bracket Set -)

  • 천득염;양태현;이재연
    • 건축역사연구
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    • 제21권2호
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    • pp.7-20
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    • 2012
  • As the corner of wooden pagoda forms the roof by closely bordering left and right eaves on the various purlins and angle rafters, it is designed for every face to be recognized as front whose structure system increases load to bear proportionally. The corner of wooden pagoda is inseparable with the corner bracket set as it becomes stable thanks to the corner bracket set structurally and load burden under restrained structure makes the corner bracket set really important. Accordingly, this study could figure out some facts by analyzing corner bracket sets of Palsangjeon of Beobjusa Temple in Korea, Seokgatap of Bulgungsa Temple in China and Ojungtap of Beobryungsa Temple in Japan which were constructed with pure wooden structure. This study demonstrated that corner bracket set played a pivotal role in keeping balance of concentrated load of corner (corner of opening) in each floor that contributed to the stability of wooden pagoda structurally despite multiple duplications of floors and also figured out the outfit of corner bracket set was subject to the floor type and the cross section of Gongpo installed on top of Pyeongju. Wooden pagodas in 3 countries were two floor types of octagon and square, and employed different connection method between upper and lower floors. The difference between floor and duplication method determines the method of corner, but even different methods were sufficient to have entirety in every side by completing dynamic principle of corner bracket set even though old method had to solve the problem of concentrated load and it also confirms that it was essential Gongpo to prevent any deformation of corner.

연속섬유 시트로 보강된 RC 부재의 모서리 형상에 따른 보강 효율에 관한 연구 (Strengthening Efficiency for the Various Corner Shapes of RC Member confined with Continuous Fiber Sheets)

  • 고훈범;이진섭
    • 한국건축시공학회지
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    • 제8권2호
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    • pp.113-119
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    • 2008
  • Recently, fiber reinforced polymers(FRP) composite materials are used extensively in the rehabilitation of concrete structural members. A main application is to wrap beams and columns using the continuous fibers sheets to improve their strength and ductility. The corner chamfering affects significantly the performance of the continuous fibers sheets, and could lead to environmental problem with waste and dust. The main purpose of this paper is to verify the effect of corner conditions on the strength of the continuous fiber sheets, and to introduce new attached components which can avoid environmental problem. A total of 15 specimens were tested and carefully checked for three types of continuous fiber sheets(carbon, glass, and aramid) and three types of corner conditions(non-chamfering, chamfering, and device attaching). It is proved that the devices proposed in this research have some capabilities to use for RC member. But additional research will be needed for commercializing.

Precise Vehicle Localization Using 3D LIDAR and GPS/DR in Urban Environment

  • Im, Jun-Hyuck;Jee, Gyu-In
    • Journal of Positioning, Navigation, and Timing
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    • 제6권1호
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    • pp.27-33
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    • 2017
  • GPS provides the positioning solution in most areas of the world. However, the position error largely occurs in the urban area due to signal attenuation, signal blockage, and multipath. Although many studies have been carried out to solve this problem, a definite solution has not yet been proposed. Therefore, research is being conducted to solve the vehicle localization problem in the urban environment by converging sensors such as cameras and Light Detection and Ranging (LIDAR). In this paper, the precise vehicle localization using 3D LIDAR (Velodyne HDL-32E) is performed in the urban area. As there are many tall buildings in the urban area and the outer walls of urban buildings consist of planes generally perpendicular to the earth's surface, the outer wall of the building meets at a vertical corner and this vertical corner can be accurately extracted using 3D LIDAR. In this paper, we describe the vertical corner extraction method using 3D LIDAR and perform the precise localization by combining the extracted corner position and GPS/DR information. The driving test was carried out in an about 4.5 km-long section near Teheran-ro, Gangnam. The lateral and longitudinal RMS position errors were 0.146 m and 0.286 m, respectively and showed very accurate localization performance.

Engineering critical assessment of RPV with nozzle corner cracks under pressurized thermal shocks

  • Li, Yuebing;Jin, Ting;Wang, Zihang;Wang, Dasheng
    • Nuclear Engineering and Technology
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    • 제52권11호
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    • pp.2638-2651
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    • 2020
  • Nozzle corner cracks present at the intersection of reactor pressure vessels (RPVs) and inlet or outlet nozzles have been a persistent problem for a number of years. The fracture analysis of such nozzle corner cracks is very important and critical for the efficient design and assessment of the structural integrity of RPVs. This paper aims to perform an engineering critical assessment of RPVs with nozzle corner cracks subjected to several transients accompanied by pressurized thermal shocks. The critical crack size of the RPV model with nozzle corner cracks under transient loading is evaluated on failure assessment curve. In particular, the influence of cladding on the crack initiation of nozzle corner crack under thermal transients is studied. The influence of primary internal pressure and secondary thermal stress on the stress field at nozzle corner and SIF at crack front is analyzed. Finally, the influence of different crack size and crack shape on the final critical crack size is analyzed.

CORNER SINGULARITY AT THE MULTIPLE JUNCTION OF THE ELECTRIC TRANSMISSION

  • Choe, Hi-Jun;Park, Kyong-Yop;Sohn, Ayoung
    • 대한수학회지
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    • 제42권6호
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    • pp.1311-1322
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    • 2005
  • We consider the several plane sector domains which are bonded together along common edges with vertex at the origin. Such domains appear in electric conducting problem with multi-layered heterogeneous media. Our aim is to give a structure theorem of the singularities of the electric field at the corner. Also, we provide a regularity theorem for the electric field.

ALGORITHMS TO APPLY FINITE ELEMENT DUAL SINGULAR FUNCTION METHOD FOR THE STOKES EQUATIONS INCLUDING CORNER SINGULARITIES

  • JANG, DEOK-KYU;PYO, JAE-HONG
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • 제23권2호
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    • pp.115-138
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    • 2019
  • The dual singular function method [DSFM] is a solver for corner sigulaity problem. We already construct DSFM in previous reserch to solve the Stokes equations including one singulairity at each reentrant corner, but we find out a crucial incorrection in the proof of well-posedness and regularity of dual singular function. The goal of this paper is to prove accuracy and well-posdness of DSFM for Stokes equations including two singulairities at each corner. We also introduce new applicable algorithms to slove multi-singulrarity problems in a complicated domain.

초등학교의 학습 및 교육활동을 위한 다기능 교실계획에 관한 연구 (A Study on the layout of multi-function classroom for the teaming activity and teaching process in elementary school)

  • 이상호;최진;김영신
    • 한국실내디자인학회논문집
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    • 제29호
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    • pp.145-152
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    • 2001
  • Open education, which has been introduced spontaneous1y to many countries, has been giving some strong influence to the primary education in Korea and has been widely used in Korea itself. This report deals with the ineffectiveness of the learning space which has been divided into common classroom and particular classroom. The division of the learning space sets the problem of defining which is the particular of common subject, and the problem of a child to move around for different subject. For the architectural design of school, it is essential for learning space to be suitable for the characteristics of each subjects. The space needed for individual subjects requires tole learning space that is different to the space needed for basic academic subjects. The introduction of different corners in the classroom can be the solution. Individual corners can be divided into the necessary coner, the standard corner, the elective corner and the corner fur facilities.

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3차원 수직 좌표계의 지반-구조물 상호작용해석을 위한 동적 무한요소의 개발 (3-DIMENSIONAL DYNAMIC INFINITE ELEMENTS IN CARTESIAN COORDINATES FOR MULTI-LAYERED HALF-SPACE)

  • 서춘교;윤정방
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2006년도 학술발표회 논문집
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    • pp.628-636
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    • 2006
  • This paper presents 3D infinite elements in Cartesian coordinates for the elastodynamic problem in multi-layered half-space. Five kinds of infinite elements are developed by using approximate expressions of multiple wave components for the wave function in exterior far-field soil region. They are horizontal, horizontal-corner, vertical, vertical-corner and vertical-horizontal-corner elements. The elements can be used for the multi-wave propagating problem. Numerical example analyses are presented for rigid disk, square footings and embedded footing on homogeneous and layered half-space. The numerical results obtained show the effectiveness of the proposed infinite elements.

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