• 제목/요약/키워드: inner system

검색결과 2,156건 처리시간 0.028초

Vision-Based Roadway Sign Recognition

  • Jiang, Gang-Yi;Park, Tae-Young;Hong, Suk-Kyo
    • Transactions on Control, Automation and Systems Engineering
    • /
    • 제2권1호
    • /
    • pp.47-55
    • /
    • 2000
  • In this paper, a vision-based roadway detection algorithm for an automated vehicle control system, based on roadway sign information on roads, is proposed. First, in order to detect roadway signs, the color scene image is enhanced under hue-invariance. Fuzzy logic is employed to simplify the enhanced color image into a binary image and the binary image is morphologically filtered. Then, an effective algorithm of locating signs based on binary rank order transform (BROT) is utilized to extract signs from the image. This algorithm performs better than those previously presented. Finally, the inner shapes of roadway signs with curving roadway direction information are recognized by neural networks. Experimental results show that the new detection algorithm is simple and robust, and performs well on real sign detection. The results also show that the neural networks used can exactly recognize the inner shapes of signs even for very noisy shapes.

  • PDF

컴퓨터 비젼을 이용한 파이프 불량 검사시스템 개발 (Development of Pipe Fault Inspection System using Computer Vision)

  • 박찬호;양순용;안경관;오현옥;이병룡
    • 제어로봇시스템학회논문지
    • /
    • 제9권10호
    • /
    • pp.822-831
    • /
    • 2003
  • A computer-vision based pipe-inspection algorithm is developed. The algorithm uses the modified Hough transformation and a line-scanning approach to identify the edge line and the radius of the pipe image, from which the eccentricity and dimension of the pipe-end is calculated. Line and circle detection was performed using Laplace operator with input image, which are acquired from the front and side cameras. In order to minimize the memory usage and the processing time, a clustering method with the modified Hough transformation is introduced for line detection. The dimension of inner and outer radius of pipe is calculated by the proposed line-scanning method. The method scans several lines along the X and Y axes, calculating the eccentricity of inner and outer circle, by which pipes with wrong end-shape can be classified and removed.

이중대역 동작을 위한 멀티모드 시나리오에서 CDMA/TDD의 성능 (Performance of CDMA/TDD in Multimode Scenario for Dual-band Operation)

  • 오형주;황승훈
    • 대한전자공학회논문지TC
    • /
    • 제45권11호
    • /
    • pp.32-36
    • /
    • 2008
  • 본 논문에서는 외부지역에서 낮은 주파수 대역으로 FDD(Frequency Division Duplex)를 사용하고 내부지역에서 TDD(Time Division Duplex)를 사용하는 이중대역 동작을 하는 멀티모드 시나리오에서 내부지역의 CDMA/TDD의 용량을 조사하였다. 특히, 셀 반경, 데이터 전송률, 타임 슬롯 할당과 같은 다양한 시스템 파라미터의 영향을 분석하였다.

PDP 유동장 PIV 계측 (PIV Measurement on the Flows of PDP(Plasma Display Panel))

  • 도덕희;조경래;송주석;백태실;편용범;정우만
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2001년도 춘계학술대회논문집E
    • /
    • pp.733-737
    • /
    • 2001
  • Heat generated from the electronic parts in PDP is undesirable physical properties. To attain optimal arrangement of the electronic parts in PDP, thermal flows in PDP should be analyzed. PIV measurement has been made to quantify the characteristics of the inner flows and outer flows of an actual PDP. The quantity of heat flux from PDP has been estimated using the PIV results. Measurement system consists of Ar-ion laser, CCD camera and an image grabber installed on a host computer.

  • PDF

Internal Model Control of UPS Inverter using Resonance Model

  • Park J. H.;Kim D. W.;Kim J. K.;Lee H. W.;Noh T. K.;Woo J. I.
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
    • /
    • pp.184-188
    • /
    • 2001
  • In this paper, a new fully digital control method for single-phase UPS inverter, which is based on the double control loop such as the outer voltage control loop and inner current control loop, is proposed. The inner current control loop is designed and implemented in the form of internal model control and takes the presence of computational time-delay into account. Therefore, this method provides an overshoot-free reference-to-output response. In the proposed scheme, the outer voltage control loop employing P controller with resonance model implemented by a DSP is introduced. The proposed resonance model has an infinite gain at resonant frequency, and it exhibits a function similar to an integrator for AC component. Thus the outer voltage control loop causes no steady state error as regard to both magnitude and phase. The effectiveness of the proposed control system has been demonstrated by the simulation and experimental results respectively.

  • PDF

롤 성형기를 이용한 금속 내부구조물 기초 실험 (A study on basis of metal inner structure by roll forming machine)

  • 김형종;정동원;최두선;제태진;박재현
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 2004년도 추계학술대회 논문집
    • /
    • pp.1452-1455
    • /
    • 2004
  • Sandwich structures, which are composed of a thick core between two thin faces, are commonly used in many engineering applications because they combine high stiffness and strength with low weight. Depending on the application of a particular sandwich structure, various types of cores can be used. The production of sandwich sheets by a rolling process, which is a more efficient and economical approach compared to other types of processes, has become an increasingly important subject of study. In this paper, we have studied the embossing structure of sheet type and developed embossing roll mold with $\Phi$3 pattern and roll forming system.

  • PDF

Missile two-loop acceleration autopilot design based on 𝓛1 adaptive output feedback control

  • He, Shao-Ming;Lin, De-Fu
    • International Journal of Aeronautical and Space Sciences
    • /
    • 제15권1호
    • /
    • pp.74-81
    • /
    • 2014
  • This article documents the design of a novel two-loop acceleration autopilot based on $\mathcal{L}_1$ adaptive output feedback control for tail-controlled missiles. The inner loop is an adaptive angle-of-attack tracking loop and the outer loop is the traditional PI controller for error compensation. A systematic low-pass filter design procedure is provided for minimum phase system and is applied to the inner loop design while the parameters of the outer loop are obtained from the multi-objective optimization problem. The effectiveness of the proposed autopilot is verified through numerical simulations under various conditions.

유동제어구조물에 의한 내만의 해수순환 모델링 (Hydraulic and Numerical Modeling of Seawater Circulation of Semi-enclosed Bay with the Flow-control Structures)

  • 김종규;강태순;김헌태
    • 한국해양공학회지
    • /
    • 제14권3호
    • /
    • pp.20-28
    • /
    • 2000
  • Using the hydraulic and numerical model of semi-enclosed bay (Chinhae Bay), the efficiencies of flow-control structures on the seawater-circulation in the inner bay were investigated. Expecially, this study was confirmed the effectiveness of the flow-control structures at the mouth and narrow channel of Chinhae Bay through the experiments. The system of flow-control structures could enhance the water exchange improvement appropriately. The results of this study can be used as the long-term and integrated environmental impact assessment model in the inner bay.

  • PDF

정체 및 유동액체에서 산소전극의 안정상태 일차원적 해석 (A Strady-State One-Dimensional Analysis of an Oxygen Electrode in Stationary and Flowing Liquid)

  • 김태진
    • KSBB Journal
    • /
    • 제4권2호
    • /
    • pp.150-156
    • /
    • 1989
  • 안정상태 일차원적 모델을 이용하여 막으로 덮힌 상업적인 산소 적극의 특성을 공기포화된 식염수에서 연구하였다. 전극은 세 개의 층으로 이루어져 있는데. 이는 외부 농도 경계층(용액), 반투성 막, 내부 전해질 용액 층으로 구분된다. 정체용액에서, 물은 외부 용액층으로부터 내부 전해질 용액쪽으로 열역학적 평형을 이룰 때까지 이동한다. 한편 유동 용액에서, 불은 수력학적 압력차 때문에 전해질 층의 두께가 막의 두께와 같아질 때까지 반대방향으로 이동한다.

  • PDF