• 제목/요약/키워드: Coordinate Change

검색결과 268건 처리시간 0.023초

Luminance Change Independent 3D Snail Tracking

  • Dewi, Primastuti;Choi, Yoen-Seok;Chon, Tae-Soo;Cha, Eui-Young
    • 한국정보통신학회:학술대회논문집
    • /
    • 한국해양정보통신학회 2010년도 추계학술대회
    • /
    • pp.175-178
    • /
    • 2010
  • Slow movement of snail can be a benefit since it means less speed of tracking is required to get accurate movement track, but in the other side it is difficult to extract the object because the snail is almost as static as the background. In this paper, we present a technique to track the snail by using one of its common characteristic, dark color of its shell. The technique needs to be robust to illumination change since the experiment is usually to observe the movement of snail both at bright and dim condition. Snail position coordinate in 3D space is calculated using orthogonal stereo vision which combines the information from two images taken from cameras at the top and in front of the aquarium. Experimental results show this technique does not need prior background image extraction and robust to gradual or sudden illumination change.

  • PDF

플렉시블 무기EL 색변환 백색 발광 소자 제작 및 특성평가 (The Fabrication and Characteristics of White Emission using CCM on Flexible Substrate)

  • 김기령;안성일;금정훈;이흥렬;임태홍;이성의
    • 한국전기전자재료학회논문지
    • /
    • 제21권10호
    • /
    • pp.911-915
    • /
    • 2008
  • EL (electro-luminescent) device as a light source has an advantage in embodying large area with great flexibility. On nickel foil as an electrode and backplane, we demonstrated a white EL flexible light source with blue phosphor layer combined with color change layer. A correlation between color change layer and color coordination was analyzed by Gaussian method, and then the color coordinate was controlled near to (0.33, 0.33) of pure white light.

상변화 물질의 용융과정에 있어서 좌표변환을 이용한 온도분포의 해석적 연구 (The finite difference analysis on temperature distribution by coordinate transformation during melting process of phase-change Material)

  • 김준근;임장순
    • 태양에너지
    • /
    • 제5권2호
    • /
    • pp.77-83
    • /
    • 1985
  • An analysis is performed to investigate the influence of the buoyancy force and the thickness variation of melting layer in the containment that is filled with phase-change Material surrounding a cylindrical heating tube during melting process. The phase-change material is assumed to be initially solid at its phase-change temperature and the remaining solid at any given time is still at the phase-change temperature and neglecting the effect of heat transfer occuring within the solid. At the start of melting process, the thickness of melting layer is assumed to be a stefan-problem and after the starting process, the change of temperature and velocity is calculated using a two dimensional finite difference method. The governing equations for velocity and temperature are solved by a finite difference method which used SIMPLE (Semi Implicit Method Pressure linked Equations) algorithm. Results are presented for a wide range of Granshof number and in accordance with the time increment and it is founded that two dimensional fluid flow occurred by natural convection decreases the velocity of melting process at the bottom of container. The larger the radius of heating tube, the higher heat transfer is occurred in the melting layer.

  • PDF

ON THE STRUCTURE OF A MUSH

  • Yang, Young-Kyun;Lee, Joung-Nam
    • 대한수학회보
    • /
    • 제41권2호
    • /
    • pp.283-297
    • /
    • 2004
  • We have obtained a simplified model for the mush under the assumption of the temperature, the solid fraction and the vertical component of the velocity, depend on upward coordinate z only. We have found solutions in the asymptotical limit and solved numerically for the model.

Modeling of the Centerless Through-feed Grinding Process

  • Kim, Kang
    • Journal of Mechanical Science and Technology
    • /
    • 제17권7호
    • /
    • pp.1036-1043
    • /
    • 2003
  • A computer simulation method for investigating the form generation mechanism in the centerless through-feed grinding process is described. The length of the contact line and the magnitude of the grinding force between the grinding wheel and workpieces, vary with the change in the axial location of the current workpiece during grinding. Thus, a new coordinate system and a grinding force curve of previous and/or following workpieces are introduced to treat the axial motion. Experiments and computer simulations were carried out using four types of cylindrical workpiece shapes. To validate this model, simulation results are compared with the experimental results.

무궤도 자율 AGV 개발 (Autonomous AGV for automation)

  • 표종훈;최진욱;한민홍
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 제어로봇시스템학회 1992년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 19-21 Oct. 1992
    • /
    • pp.13-18
    • /
    • 1992
  • In this study, we developed an autonomous AGV which carries materials between workshops. In most of existing AGV systems, when AGV is required to change its navigating path, the guideline or landmark of AGV should be rebuilt according to new navigating path. Using sensors and internal coordinate system, our AGV, however, can navigate along the new path by only changing input parameters of program. On navigating, if AGV meets obstacles, it avoids them and go on to the destination.

  • PDF

비선형 저차화 관측기의 설계기법 및 구보시스템에의 적용 (A Nonlinear Reduced Order Observer Design and Its Application to Ball and Beam System)

  • 조남훈
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제53권9호
    • /
    • pp.630-637
    • /
    • 2004
  • In this paper, we present a local reduced-order observer for a class of nonlinear systems that have full robust relative degree. The proposed observer utilizes the coordinate change which transforms a nonlinear system into an approximate normal form. The proposed reduce order observer is applied to a ball and beam system, and simulation results show that substantial improvement in the performance was achieved compared with the jacobian linearization observers.

Spatial Distribution of Excited Argon Species in and Inductively Coupled Plasma

  • 최범석
    • Bulletin of the Korean Chemical Society
    • /
    • 제19권11호
    • /
    • pp.1172-1174
    • /
    • 1998
  • Spatial(radial and height) distributions of excited argon species are measured for an inductively coupled plasma under five operating conditions: 1) no carrier gas, 2) carrier gas without aerosol, 3) carrier gas with desolvated aerosol, 4) carrier gas with aerosol, 5) carrier gas with aerosol and excess lithium. A complete RF power mapping of argon excited states is obtained. The excited states of argon for a typical analytical torch rapidly diffuse towards the center in the higher region of the plasma. The presence of excess lithium makes no significant change in the excited states of argon. The increase in the RF power increases the intensity of argon excited states uniformly across the radial coordinate.

보행 시 노인의 상체 움직임에 대한 3차원적 분석 (The Three Dimensional Analysis of the Upper Body's Segments of the Elderly during Walking)

  • 김희수;윤희중;류지선;김태삼
    • 한국운동역학회지
    • /
    • 제14권3호
    • /
    • pp.1-15
    • /
    • 2004
  • The purpose of this study was to investigate the kinematic variables of the upper part of the body for 8 elderly men during walking. For this study, kinematic data were collected using a six-camera (240Hz) Qualisys ProReflex system. The room coordinate system was right-handed and fixed in space, with righted orthogonal segment coordinate systems defined for the head, trunk, and pelvis. Based on a rigid body model, reflective marker triads were attached on the 3 segments. Three-dimensional Cartesian coordinates for each marker were determined at the time of recording using a nonlinear transformation(NLT) technique with ProReflex software (Qualisys, Inc.). Coordinate data were low-pass filtered using a fourth-order Butterworth with cutoff frequency of 6Hz. Three-dimensional angles of the head, trunk, and pelvis segment were determined using a Cardan method. On the basis of each segment angle, angle-angle plot used to estimated the movement coordinations between segments. The conclusions were as follows; (1) During the support phase of walking, the elderly people generally kept their, head the flexional and abductional posture. Particularly, the elderly displayed little internal/external rotation. (2) The elderly people showed extensional and external rotation postures in the trunk movement. Particularly, It showed the change from adduction into abduction at the heel contact event of the stance phase. (3) The elderly people showed almost same pelvis movement from the flexion into extension, from the abduction into adduction, and from internal rotation into external rotation at the mid stance and toe off of the stance phase.

시각 센서에 의한 로봇 매니퓰레이터의 툴 좌표계 보정에 관한 연구 (The Tool Coordinate Adjustment Algorithm for Robot Manipulators with Visual Sensor)

  • 이용중;김학범;이양범
    • 한국통신학회논문지
    • /
    • 제19권8호
    • /
    • pp.1453-1463
    • /
    • 1994
  • 본 연구에서는 로보트 시스템에게 인식기능을 부여하여 작업대상물의 위치와 방향이 임의적으로 변경되어도 사용자가 원하는 핸들링작업을 원활하게 수행할 수 있는 자동화시스템을 구현하는데 있다. 이를 위하여 작업대상물의 변화된 위치와 방향은 시각센서로서 검출하고, 화상처리과정에서 명도정보의 가변과 같은 주변여건의 변화때문에 발생하는 에지 추적 오차는 적절한 필터링 방법을 적용하여 최소화시켰다. 시각센서의 운용 프로그램은 인터럽트 기법으로 주변장치와 상호제어가 가능토록 구성하고, 시각센서에서 검출한 데이타는 아스키 포멧으로 로보트시스템에 전달되어 6자유도 매니플레이터의 툴 좌표계는 검출데이타와 비례하게 자동보성되어 작업대상물의 위치와 방향변화를 추종할 수 있도록 개발하였다. 본 연구에서 개발한 시스템 운용 알고리즘을 생산현장에 직접 적용한 결과 라인 밸런스의 향상과 산업재해방지를 위한 효과적이고 안정된 생산설비로써 운용될 수 있었다.

  • PDF