• 대한조선학회논문집
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• 제42권5호
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• pp.466-471
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• 2005

The out-of-plane deformation in thin plate structure has been a serious qualify problem. It has been known that the out-of-plane deformation is caused by the angular deformation of welded joint. However, experimental results show that the conventional theory based on angular deformation is not appropriate for prediction of the out-of-plane deformation in thin plate structure. In this study, large deformation plate theory is introduced to clarify the effect of residual stress on the out-of-plane deformation. A simple equation is proposed to predict the out-of-plane deformation. The results by the proposed method show good agreement with the experimental results.

• 대한조선학회논문집
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• 제55권6호
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• pp.521-526
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• 2018

The doubler plate design system for the reinforcement of the ship plate members was developed considering various loads that subjected to the in-plane biaxial load, the in-plane shear load and out-of-plane load. The author summarized the accuracy of the development formula and equations through the equivalent plate thickness concept and finally introduced the new design system of doubler plate reinforcement. Through this study, it can be considered as an initial design guideline based on ship doubler plate reinforcement strength at areas without repeated load, or an initial structure analysis model for final structural design.

• 한국산업정보학회논문지
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• 제22권3호
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• pp.39-47
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• 2017

깊이 화면을 부호화함에 있어서 깊이 화면의 일부를 평면으로 추정하여 부호화하는 평면 부호화 모드를 적용할 수 있다. 본 논문에서는 평면 부호화 모드를 통한 깊이 영상 부호화에서 가변 블록 부호화를 위해 가변 블록 크기를 결정하는 방법을 제안한다. 깊이를 통해 블록 내 화소에 대해 제일 근접한 평면을 추정하는 방법을 통해 평면 부호화를 수행할 수 있다. 평면 부호화를 수행할 때, 가변 블록 부호화를 다음과 같이 적용할 수 있다. 먼저 최대 블록 크기에 대하여 추정 오차를 계산한 뒤 오차가 임계값 이하라면 해당 블록 크기가 선택 된다. 반면 오차가 임계값을 초과한다면 해당 블록이 분할되고 위 과정을 반복한다. 분할된 블록 크기가 최소 블록 크기 미만이 되면 해당 블록은 평면 부호화 모드로 선택되지 않는다. 제안된 방법을 실험한 결과, 부호화하여야 할 블록의 개수가 평면으로 이루어진 영상에서 고정 블록 크기를 이용한 방법에 비해 19%로 줄었다.

• 조명전기설비학회논문지
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• 제16권4호
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• pp.73-79
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• 2002

본 논문는 공기중 교류전압원을 이용하여 3종류의 전극부(침대평판전극, 평판대평판전극 및 구대평판전극부)에서 방전시 방사되는 방사전자파를 측정하고, 그 스펙트럼의 특이한 패턴을 나타냈다. 방사전자파의 측정은 스펙트럼분석기와 바이코니칼 안테나를 사용하여 VHF(30~230[MHz])대역에서 측정하였다. 방전개시전압영역일 때, 침대평판전극부인 경우에는 주파수 45, 70, 80[MHz] 대역에서, 평판대평판전극과 구대평판전극부인 경우에는 주파수40[MHz]에서 높은 전계강도를 나타내었다. 그러나 절연파괴전압영역일 때, 방사전자파의 주파수 스펙트럼분포는 전극의 형태에 따라 측정주파수 영역에서 차이를 나타내었다.

• 전기학회논문지
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• 제57권11호
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• pp.2086-2094
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• 2008

Finding a planar surface on 3D space is very important for efficient and safe operation of a mobile robot. In this paper, we propose a method using a plane detection cell (PDC) and iterative randomized Hough transform (IRHT) for finding the planar region from a 3D range image. First, the local planar region is detected by a PDC from the target area of the range image. Each plane is then segmented by analyzing the accumulated peaks from voting the local direction and position information of the local PDC in Hough space to reduce effect of noises and outliers and improve the efficiency of the HT. When segmenting each plane region, the IRHT repeatedly decreases the size of the planar region used for voting in the Hough parameter space in order to reduce the effect of noise and solve the local maxima problem in the parameter space. In general, range images have many planes of different normal directions. Hence, we first detected the largest plane region and then the remained region is again processed. Through this procedure, we can segment all planar regions of interest in the range image.

• 한국재료학회지
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• 제28권4호
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• pp.208-213
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• 2018

Epitaxial ($11{\bar{2}}0$) a-plane GaN films were grown on a ($1{\bar{1}}02$) R-plane sapphire substrate with photoresist (PR) masks using metal organic chemical vapor deposition (MOCVD). The PR mask with striped patterns was prepared using an ex-situ lithography process, whereas carbonization and heat treatment of the PR mask were carried out using an in-situ MOCVD. The heat treatment of the PR mask was continuously conducted in ambient $H_2/NH_3$ mixture gas at $1140^{\circ}C$ after carbonization by the pyrolysis in ambient $H_2$ at $1100^{\circ}C$. As the time of the heat treatment progressed, the striped patterns of the carbonized PR mask shrank. The heat treatment of the carbonized PR mask facilitated epitaxial lateral overgrowth (ELO) of a-plane GaN films without carbon contamination on the R-plane sapphire substrate. Thhe surface morphology of a-plane GaN films was investigated by scanning electron microscopy and atomic force microscopy. The structural characteristics of a-plane GaN films on an R-plane sapphire substrate were evaluated by ${\omega}-2{\theta}$ high-resolution X-ray diffraction. The a-plane GaN films were characterized by X-ray photoelectron spectroscopy (XPS) to determine carbon contamination from carbonized PR masks in the GaN film bulk. After $Ar^+$ ion etching, XPS spectra indicated that carbon contamination exists only in the surface region. Finally, the heat treatment of carbonized PR masks was used to grow high-quality a-plane GaN films without carbon contamination. This approach showed the promising potential of the ELO process by using a PR mask.

• 한국차세대컴퓨팅학회논문지
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• 제15권4호
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• pp.80-88
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• 2019

소프트웨어 정의 네트워킹(SDN)은 네트워크 장치의 데이터 기능과 제어기능을 분리한 미래 네트워킹 기술이다. 네트워크 장치들이 하나의 컨트롤러에 의해 중앙 제어되는 SDN의 구조는 대규모의 네트워크로의 확장성을 보장하기가 쉽지 않다. 선행연구들은 다수의 컨트롤러를 배치하는 수평적 확장성에 초점을 두어왔다. 이 연구들은 제어 평면과 응용 평면을 하나의 컨트롤러로 추상화하고 있다. 보편적인 SDN 아키텍처의 계층은 데이터 평면, 제어 평면, 응용 평면으로 나뉘는데 응용평면과 제어평면은 논리적으로 분리되어 있음에도 두 평면을 하나의 컨트롤러로 간주하였다. 따라서 본 논문에서는 대기행령 이론을 바탕으로 제어 평면과 응용 평면을 분리하여 반영한 트래픽 성능 분석 모델을 제안한다. 이 모델을 사용하면 복잡한 시뮬레이션 대신 간단하게 컨트롤러 배치 문제 등과 같은 확장성 문제에 활용할 수 있다.

• Imaging Science in Dentistry
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• 제51권4호
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• pp.389-398
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• 2021

Purpose: This study introduces a standardized 2-plane approach using 8 landmarks to assess alveolar bone levels in mice using micro-computed tomography. Materials and Methods: Bone level differences were described as distance from the cemento-enamel junction (CEJ) to alveolar bone crest (ABC) and as percentages of vertical bone height and vertical bone loss, comparing mice infected with Porphyromonas gingivalis (Pg) to controls. Eight measurements were obtained per tooth: 2 in the sagittal plane (mesial and distal) and 6 in the coronal plane (mesiobuccal, middle-buccal, distobuccal, mesiolingual, middle-lingual, and distolingual). Results: Significant differences in the CEJ-to-ABC distance between Pg-infected mice and controls were found in the coronal plane (middle-lingual, mesiobuccal, and distolingual for the first molar; and mesiobuccal, middle-buccal, and distolingual for the second molar). In the sagittal plane, the distal measurement of the second molar was different. The middle-buccal, mesiobuccal, and distolingual sites of the first and second molars showed vertical bone loss relative to controls; the second molar middle-lingual site was also different. In the sagittal plane, the mesial sites of the first and second molars and the distal site of the second molar showed loss. Significantly different vertical bone height percentages were found for the mesial and distal sites of the second molar (sagittal plane) and the middle-lingual and distolingual sites of the first molar(coronal plane). Conclusion: A reliable, standardized technique for linear periodontal assessments in mice is described. Alveolar bone loss occurred mostly on the lingual surface of the coronal plane, which is often omitted in studies.

• Korean Journal of Mathematics
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• 제30권4호
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• pp.643-652
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• 2022

In this paper, we will describe affine homogeneous domains in the complex plane. For this study, we deal with the Lie algebra of infinitesimal affine transformations, a structure of the hyperbolic metric involved with affine automorphisms. As a consequence, an affine homogeneous domain is affine equivalent to the complex plane, the punctured plane or the half plane.

• 한국공작기계학회논문집
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• 제12권2호
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• pp.53-58
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• 2003

It is very important to measure linear cycle plane positioning accuracy of NC lathe as it effects all other parts of machines machined by them in industries. If the plane positioning accuracy of NC lathe is bad, the dimension accuracy and the change-ability of works will be bad in the assembly of machine parts. In this paper, computer software systems are organized to measure linear cycle plane positioning displacement of ATC(Automatic tool changer) on zx plane of NC lathe using two linear scales. And each sets of error data obtained from the test is descriptions to plots and the results of linear cycle plane positioning errors are expressed as nutriments by computer treatment.