• 제목/요약/키워드: Moving Surface method

검색결과 390건 처리시간 0.024초

연결 성분 분석과 크기 정규화를 이용한 도로 노면 표시와 숫자 인식 (Recognition of Road Surface Marks and Numbers Using Connected Component Analysis and Size Normalization)

  • 정민철
    • 반도체디스플레이기술학회지
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    • 제21권1호
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    • pp.22-26
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    • 2022
  • This paper proposes a new method for the recognition of road surface marks and numbers. The proposed method designates a region of interest on the road surface without first detecting a lane. The road surface markings are extracted by location and size using a connection component analysis. Distortion due to the perspective effect is minimized by normalizing the size of the road markings. The road surface marking of the connected component is recognized by matching it with the stored road marking templates. The proposed method is implemented using C language in Raspberry Pi 4 system with a camera module for a real-time image processing. The system was fixedly installed in a moving vehicle, and it recorded a video like a vehicle black box. Each frame of the recorded video was extracted, and then the proposed method was tested. The results show that the proposed method is successful for the recognition of road surface marks and numbers.

2D Laser Scanner 포인트의 자동 분리를 통한 이동체의 구분에 관한 연구 (A Study on the recognition of moving objects by segmenting 2D Laser Scanner points)

  • 이상엽;한수희;유기윤
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2006년도 춘계학술발표회 논문집
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    • pp.177-180
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    • 2006
  • In this paper we proposed a method of automatic point segmentation acquired by 2D laser scanner to recognize moving objects. Recently, Laser scanner is noticed as a new method in the field of close range 3D modeling. But the majority of the researches are pointed on precise 3D modeling of static objects using expensive 3D laser scanner. 2D laser scanner is relatively cheap and can obtain 2D coordinate information of moving object's surface or can be utilized as 3D laser scanner by rotating the system body. In these reasons, some researches are in progress, which are adopting 2D laser scanner to robot control systems or detection of objects moving along linear trajectory. In our study, we automatically segmented point data of 2D laser scanner thus we could recognize each of the object passing through a section.

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가변 속도 이동식 마스크를 이용한 렌즈 곡면 형성 (Generation of Lens surface by moving mask lithography)

  • 이준섭;박우제;송석호;오차환;김필수
    • 한국광학회지
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    • 제16권6호
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    • pp.508-515
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    • 2005
  • MEMS 공정을 이용한 굴절렌즈 제작을 위하여, 슬릿 패턴을 갖는 마스크를 이동시키며 노광을 하는 가변 속도 이동식 마스크에 의한 노광 방법을 제안하였다. 감광제 면이 굴절렌즈의 곡면을 이루려면 감광제의 위치에 따른 노광 에너지의 분포를 조절해야 한다. 마스크의 패턴 형태와 이동 속돈 방향에 따라 감광제의 위치에 따른 노광 에너지의 분포를 이론적으로 분석하였으며, 감광제 박막에 임의의 곡면을 갖는 굴절렌즈 형상을 형성할 수 있음을 실험적으로 확인하였다. $100 {\mu}m$ 이상의 후막 감광제를 이용하거나, 혹은 곡면 형상을 갖는 얇은 감광제 형상을 마스크로 하여 이온식각을 수행하여 수백 ${\mu}m$ 정도의 최대높이를 갖는 렌즈 곡면형상을 제작 할 수 있었다.

Moving Mesh Technique을 이용한 2차원 염해 침투 예측 모델의 개발 (Development of Two Dimensional Chloride Ion Penetration Model Using Moving Mesh Technique)

  • 최원;김한중
    • 한국농공학회논문집
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    • 제57권6호
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    • pp.1-7
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    • 2015
  • Most of chloride diffusion models based on finite difference method (FDM) could not express the diffusion in horizontal direction at each elevation. To overcome these weakness, two dimensional chloride ion penetration model based on finite element method (FEM) to be able to combine various multi-physics simultaneously was suggested by introducing moving mesh technique. To avoid the generation of mesh being able to be distorted depending on the relative movement of water level to static concrete, a rectangular type of mesh was intentionally adopted and the total number of meshes was empirically selected. The simulated results showed that the contents of surface chloride decreased following to the increase of elevation in the top part of low sea level, whereas there were no changes in the bottom part of low level. In the DuraCrete model, the diffusion coefficient of splashed zone is generally smaller than submerged zone, whereas the trend of Life365 model is reverse. Therefore, it could be understood that the developed model using moving mesh technique effectively reflects $DuraCrete^{TM}$ model rather than $Life365^{TM}$ model. In the future, the model will be easily expanded to be combined with various multi-physics models considering water evaporation, heat of hydration, irradiation effect of sun and so on because it is based on FEM.

멀티 레이저 라인을 이용한 비등속 이동물체의 3차원 표면 모델링 (3D Surface Modeling of Moving Object Using Multi-Laser Lining)

  • 이영열;김효성;변기원;남기곤;이철헌
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2006년도 하계종합학술대회
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    • pp.409-410
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    • 2006
  • We propose a surface modeling method using multi-laser lining. We can acquire 3D surface by analyzing projected laser lines on object. The laser lines reflect the surface curvature. In this paper, we show two novel approaches to reconstruct 3D shape of moving object. One is used for robust laser line extraction, and the other for registration between 3D shapes.

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출력선가동자의 구조변경에 의해 향상된 전압제어 특성을 갖는 SVR의 제작 (Fabrication of the SVR with the Improved Voltage Regulating Characteristics by the Structural Modification of the Output Wire Moving Shaft)

  • 홍성훈;강문성
    • 제어로봇시스템학회논문지
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    • 제8권10호
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    • pp.867-873
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    • 2002
  • We have designed and fabricated the slidacs type automatic voltage regulator(SVR) that is able to control the output voltage continuously according to load variation. Especially, the frictions between the surface of contact of the slidacs coils and the output wire moving shaft arc reduced by modifying the mechanical configuration of surface of contact of slidacs from the conventional sliding one into the proposed rotary one composed of cylindrical bearing. Thus, SVR using cylindrical bearing proposed in this study has less noise than the conventional one owing to the reduction of friction, and its breakdown ratio caused by the abrasion of contact materials is reduced as well. We have designed U motor driving circuit for controlling the output wire moving shaft, and introduced the digital control method using the pulse width modulation(PWM) output for controlling DC motor.

ABLATING AND CHARRING OF TWO DIMENSIONAL HEAT SHIELD MATERIALS

  • Shabani Mohammad Reza;Rahimian Mohammad Hassan
    • 한국전산유체공학회지
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    • 제10권1호
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    • pp.16-23
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    • 2005
  • The objective of this research is to estimate two dimensional ablating and charring of heat shield materials in severe aero-thermal heat transfer. This estimation requires an accurate and rapid technique for its serious heat transfer with a moving boundary. Aerodynamic heating is obtained by an explicit relation which is a function of Mach number and air condition, while a fully implicit method is used for heat transfer calculations. Moving boundary is captured by FLIAR method which is a subgroup of VOF. Thickness of ablating and charring of heat shield, temperature of the moving surface and rate of radiation heat are calculated and compared with references. The results are in good agreement with other calculations.

Optimum Design of BLDC Motor for Cogging Torque Minimization Using Genetic Algorithm and Response Surface Method

  • Jeon, Mun-Ho;Kim, Dong-Hun;Kim, Chang-Eob
    • Journal of Electrical Engineering and Technology
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    • 제1권4호
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    • pp.466-471
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    • 2006
  • This raper presents a new optimization method combining the genetic algorithm with the response surface method for the optimum design of a Brushless Direct Current motor. The method utilizes a regression function approximating an objective function and the window moving and zoom-in method so as to complement disadvantages of both the genetic algorithm and response surface method. The results verify that the proposed method is powerful and effective in reducing cogging torque by optimizing only a few decisive design factors compared with the conventional stochastic methods.

반도체 레이저 비임을 이용한 금속표면의 거칠기 측정에 관한 연구 (A Study on the Metallic Surface Roughness Measurement by Laser Diode Beam)

  • 김희남;김양술;박희재;황재연
    • 한국안전학회지
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    • 제7권4호
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    • pp.73-83
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    • 1992
  • A new technique for the measurement of surface roughness based on the Intensity fluctuations of laser light backscattered form a moving surface has been introduced. The developed method will be quite useful for evaluating the surface quality under machining with more detailed Information by detecting the surface roughness along both directions simultaneously.

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바닥의 움직임에 따른 선형파의 생성을 모의할 수 있는 간편 수치해석 기법 (A Simplified Numerical Method for Simulating the Generation of Linear Waves by a Moving Bottom)

  • 정재상
    • 한국해안·해양공학회논문집
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    • 제35권2호
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    • pp.41-48
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    • 2023
  • 본 연구에서는 바닥의 움직임에 따른 파랑의 생성 및 변화를 모의할 수 있는 간단한 선형 수치해석 기법을 소개한다. 연속방정식과 선형의 동역학적 및 운동학적 자유수면 경계조건, 선형의 운동학적 바닥 경계조건을 공간에 대해 푸리에 변환한 후 파수 영역에서 수치해석을 수행하며, 결과는 푸리에 역변환을 통해 공간영역에서 표현된다. 파수 영역에서 동역학적 자유수면 경계조건과 운동학적 자유수면 경계조건이 수치적으로 계산되며, 이 때 평균수면 (z = 0)에서의 속도포텐셜은 연속방정식과 운동학적 바닥 경계조건을 만족한다. 삼각형 및 사각형 형상의 바닥이 주기적으로 움직이는 경우의 파랑 생성 및 전파에 대해 검토하였다. 간편 수치해석 기법을 이용한 결과는 기존의 선형 해석해와 비교하였으며, 거의 일치하는 결과를 보였다. 계산 시간간격(Δt)과 계산 파수간격(Δk)에 따른 수치해석 결과의 안정성에 대해서도 검토하였다. 검토 결과 Δt ≤T(주기)/1000, Δk ≤ π/100 일 때 수치해석에 의한 결과가 적절하게 도출되는 것으로 나타났다.