• Title/Summary/Keyword: planes

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A Study on the Quasi-Sliding Mode Condition in Discrete Time Variable Structure Systems (아산시간 가변구조 시스템에서 준 슬라이딩 모드 조건에 관한 연구)

  • 이강웅;최계근
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.25 no.8
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    • pp.899-905
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    • 1988
  • In this paper, we suggest a new quasi-sliding mode condition with a wighting factor which guarantees all the states to reach switching planes and improves the convergence of the state trajectories. The result of computer simulation shows that by the suitable selection of a weighting factor, all the state trajectories reach switching planes and enter the sliding mode having the property of the insensitivity to parameter variation and disturbances.

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Fracture analysis of weld specimen using 3-dimensional finite element method (3차원 유한요소법을 이용한 용접시편의 파괴 해석)

  • Yang Seung-Yong;Goo Byeong-choon
    • Proceedings of the KSR Conference
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    • 2005.05a
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    • pp.385-390
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    • 2005
  • A specimen with residual stress due to welding was analyzed by three-dimensional cohesive zone model. The residual stress distribution was calculated by simulating welding process, and cohesive elements were located along crack propagation planes. Crack growth is possible since two planes of the cohesive element are separated beyond a maximum load carrying capacity. Stress fields around a crack tip are compared for specimens with and without residual stresses. Load-displacement curves and crack growth behaviors are also examined.

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EFFICIENTLY COMPUTING TORUS CHARTS IN LANDAU-GINZBURG MODELS OF COMPLETE INTERSECTIONS IN GRASSMANNIANS OF PLANES

  • Prince, Thomas
    • Bulletin of the Korean Mathematical Society
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    • v.54 no.5
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    • pp.1719-1724
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    • 2017
  • In this note, companion to the paper [10], we describe an alternative method for finding Laurent polynomials mirror-dual to complete intersections in Grassmannians of planes, in the sense discussed in [10]. This calculation follows a general method for finding torus charts on Hori-Vafa mirrors to complete intersections in toric varieties, detailed in [5] generalising the method of [8].

Evaluation of the Efficiency of an Inverse Exponential Kernel Estimator for Spherical Data

  • Park, Hyun Suk
    • Communications for Statistical Applications and Methods
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    • v.20 no.1
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    • pp.77-84
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    • 2013
  • This paper deals with the relative efficiency of two kernel estimators $\hat{f}_n$ and $\hat{g}_n$ by using spherical data, as proposed by Park (2012), and Bai et al. (1988), respectively. For this, we suggest the computing flows for the relative efficiency on the 2-dimensional unit sphere. An evaluation procedure between two estimators (given the same kernels) is also illustrated through the observed data on normals to the orbital planes of long-period comets.

PROPERTIES OF POSITIVE SOLUTIONS FOR THE FRACTIONAL LAPLACIAN SYSTEMS WITH POSITIVE-NEGATIVE MIXED POWERS

  • Zhongxue Lu;Mengjia Niu;Yuanyuan Shen;Anjie Yuan
    • Journal of the Korean Mathematical Society
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    • v.61 no.3
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    • pp.445-459
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    • 2024
  • In this paper, by establishing the direct method of moving planes for the fractional Laplacian system with positive-negative mixed powers, we obtain the radial symmetry and monotonicity of the positive solutions for the fractional Laplacian systems with positive-negative mixed powers in the whole space. We also give two special cases.

The Large Capacity Steganography Using Adaptive Threshold on Bit Planes (비트 플레인별 적응적 임계값을 이용한 대용량 스테가노그라피)

  • Lee, Sin-Joo;Jung, Sung-Hwan
    • The KIPS Transactions:PartB
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    • v.11B no.4
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    • pp.395-402
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    • 2004
  • In this paper, we proposed a new method of the large capacity steganography using adaptive threshold on bit planes. Applying fixing threshold, if we insert information into all bit planes, all bit planes showed different image quality. Therefore, we first defined the bit plane weight to solve the fixing threshold problem. We then proposed a new adaptive threshold method using the bit plane weight and the average complexity to increase insertion capacity adaptively. In the experiment, we inserted information into the standard images with the same image quality and same insertion capacity, and we analyzed the insertion capacity and image duality. As a result, the proposed method increased the insertion capacity of about 6% and improved the image quality of about 24dB than fixed threshold method.

3D image mosaicking technique using multiple planes for urban visualization (복수 투영면을 사용한 도심지 가시화용 3 차원 모자이크 기술)

  • CHON Jaechoon;KIM Hyongsuk
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.42 no.3 s.303
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    • pp.41-50
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    • 2005
  • A novel image mosaicking technique suitable for 3D urban visualization is proposed. It is not effective to apply 2D image mosaicking techniques for urban visualization when, for example, one is filming a sequence of images from a side-looking video camera along a road in an urban area. The proposed method presents the roadside scene captured by a side-looking video camera as a continuous set of textured planar faces, which are termed 'multiple planes' in this paper. The exterior parameters of each frame are first calculated through automatically selected matching feature points. The matching feature points are also used to estimate a plane approximation of the scene geometry for each frame. These planes are concatenated to create an approximate model on which images are back-projected as textures. Here, we demonstrate algorithm that creates efficient image mosaics in 3D space from a sequence of real images.

Validity of Horizontal Reference Planes on Cone-Beam Computed Tomography Generated Postero-Anterior Cephalogram (Cone-beam CT영상으로부터 얻어진 정모두부방사선사진에서 수평기준선의 설정)

  • Kang, Hee-Jea;Kim, Jong-Ryoul;Kim, Yong-Il
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.33 no.4
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    • pp.346-351
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    • 2011
  • Purpose: The purpose of this study was to measure the angular differences between the horizontal reference planes on the CBCT generated PA cephalogram and the modified interpupillary plane, which was usually used in the clinical examination, and to evaluate the validity of the horizontal reference planes. Methods: The CBCT generated PA cephalogram was used to measure the angles between the FH, Lo and IP planes. The subjects consisted of 42 patients with facial asymmetry (males: 21, females: 21, mean-age: 21.6 years). The control groups were also assessed (males: 10, females: 10, mean-age: 23.8 years). The distance of the interpupil was measured on the soft-tissue volume rendered image. The angular differences were statistically analyzed using the $Mann-Whitney$ $U$ $test$ for inter-group comparisons and the $Friedman$ $test$ for intra-group comparisions. Results: The angle between the FH plane and IP plane (the angle of the FH-IP line) showed a statistically significant difference between the two groups ($p$ <0.05). There was no statistical differences between each angle (angle of the FH-IP line, angle of the FH-Lo line, angle of the Lo-IP line) on the intra-group comparision ($p$ >0.05). Conclusion: The angle between the Lo line and IP line (angle of the Lo-IP line) showed no statistically significant difference in both the control and asymmetry groups. Therefore, the Lo line could be used as a horizontal reference plane in CBCT generated PA cephalograms.

A STUDY OF THE STRESS DISTRIBUTION ACCORDING TO THE SLOPES OF THE CHIDING PLANES OF THE ABUTMENTS (지대치 유도면의 기울기에 따른 응력 분포에 대한 연구)

  • Lee, Cheong-Hee
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.2
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    • pp.293-301
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    • 1998
  • The purpose of this study was to investigate the effects of load on root that was applied to edentulous area in three simulated situation, in each case the guiding planes of abutment were right vertical, 95 degrees, or 100 degrees to residual ridge. The 2-dimensional finite element method was used and the finite element model was prepared as fellows. Right mandibular 1st and 2nd molar was lost and the 2nd premolar with distal rest was used as primary abutment which had three different degrees of guiding plane. Then 150N of compressive force was applied to central fossae of the 1st and 2nd molars and von Mises stress and displacement was measured. The results were as follows; 1. Irrespective of slopes of guiding planes, the stress was concentrated on mesial side of root apex and distal side of coronal portion of root, in particular on junction with distal alveolar bone. As slopes of guiding planes were increased. stress on root and compact bone surrounding abutment was increased but no considerable effect was seen on compact bone of residual ridge. 2. Distal side of coronal portion of root limited by periodontal ligament was displaced distally and mesial side of apical portion was mesially. With slope of guiding plane increasing, the pattern of displacement was similar with one another but the quantity was increased. 3. Both abutment & alveolar bone were displaced downward and root of abutment, especially distal side of coronal portion, was displaced severely. As the guiding plane was tiffed more mesially over $90^{\circ}$, the degree of displacement was also increased.

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