• Title/Summary/Keyword: error control

Search Result 6,557, Processing Time 0.039 seconds

Error Control Scheme for High-Speed DVD Systems

  • Lee, Joon-Yun;Lee, Jae-Jin;Park, Tae-Geun
    • 정보저장시스템학회:학술대회논문집
    • /
    • 2005.10a
    • /
    • pp.103-110
    • /
    • 2005
  • We present a powerful error control decoder which can be used in all of the commercial DVD systems. The decoder exploits the error information from the modulation decoder in order to increase the error correcting capability. We can identify that the modulation decoder in DVD system can detect errors more than $60\%$ of total errors when burst errors are occurred. In results, fur a decoded block, error correcting capability of the proposed scheme is improved up to $25\%$ more than that of the original error control decoder. In addition, the more the burst error length is increased, the better the decoder performance. Also, a pipeline-balanced RSPC decoder with a low hardware complexity is designed to maximize the throughput. The maximum throughput of the RSPC decoder is 740Mbps@100MHz and the number of gate counts is 20.3K for RS (182, 172, 11) decoder and 30.7K for RS (208, 192, 17) decoder, respectively

  • PDF

Performance Analysis of Network-based Data Transmission Protocol between Railway Signaling and SCADA Systems (열차제어시스템과 SCADA 장치간 네트워크 기반 데이터 전송 프로토콜의 성능분석)

  • Hwang, Jong-Gyu;Lee, Jae-Ho;Jo, Hyun-Jeong;Lee, Jong-Woo
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.55 no.9
    • /
    • pp.485-490
    • /
    • 2006
  • According to the computerization of railway signaling systems, the interface link between the signaling systems has been replaced by the digital communication channel. At the same time, the importance of the communication link is more pronounced than before. In this paper, new Network-based protocol between railway signaling and SCADA (Supervisory Control and Data Acquisition system) has designed and the overview of designed protocol is briefly represented. And also this paper addresses analysis of newly designed train control systems. Fame error rates of the data transmissions are calculated and compared for the two cases that the CTC (Centralized Traffic Control)/SCADA has an extra data transmission error control (CRC16) besides the inherent error control of the Ethernet and that the CTC/SCADA has no extra data transmission error control. With simulation results it has been verified that the additional error control code contributes to lowering the frame error rate. It will be expected to increase the safety, reliability and efficiency of maintenance of the signaling systems by using the designed protocol for railway signaling system.

Active Noise Control using Constrained Filtered-x LMS Algorithm (제한 Filtered-x LMS 알고리즘을 이용한 능동 소음제어)

  • 나희승;박영진
    • Journal of KSNVE
    • /
    • v.8 no.3
    • /
    • pp.485-493
    • /
    • 1998
  • Many of the adaptive noise control systems utilize a form of the least mean square (LMS) algorithms. In the active control of noise, it is common practice to locate an error microphone far from the control source to avoid the near-field effects by evanescent waves. Such a distance between the control source and the error microphone makes a certain level of time-delay inevitable and, hence, may yield undesirable effects on the convergence properties of control algorithms such as filtered-x LMS. This paper discusses the dependence of the convergence rate on the acoustic error path in these popularalgorithms and introduces new algorithms which increase the convergence region regardless of the time-delay in the acoustic error path. Performances of the new LMS algorithms are presented in comparison with those by the conventional algorithms based on computer simulations and experiments.

  • PDF

Error Analysis and Compensation of Measurement Delay in INS/GPS Integrated Systems with Kalman Filtering (칼만필터를 사용하는 INS/GPS 결합시스템에서 측정치 지연에 의한 오차 분석 및 보상)

  • Park, Chan-Gook;Cho, Seong-Yun;Jin, Yong
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.6 no.11
    • /
    • pp.1039-1044
    • /
    • 2000
  • In this paper, the error caused by the measurement delay in INS/GPS integrated systems with Kalman filtering is defined and analyzed through the analytical method and the simulation. It is proved that the error of measurement delay causes not only the position error but also the estimate error of the x-axis accelerometer bias when a vehicle turns. And the estimation method of the delay time and the compensation method using an extrapolation method are presented. The performance of the compensation method is shown by the analytic method and the simulation.

  • PDF

Novel Model Following Sliding Mode Controller with Virtual State (새로운 모델 추종 슬라이딩 모드 제어기)

  • Park, Seung-Kyu;Ok, In-Jo;Ahn, Ho-Kyun
    • Proceedings of the KIEE Conference
    • /
    • 2000.07d
    • /
    • pp.2669-2671
    • /
    • 2000
  • In this paper, a new model error following sliding mode control is considered with a novel sliding surface for the error. This novel sliding surface has nominal dynamics of an original state of the error system and makes it possible that the Sliding Mode Control(SMC) technique for the error of the model following is used with the various types of controllers. Its design is based on the augmented system whose dynamics have a higher order than that of the original error system. The reaching phase is removed by using an initial virtual state which makes the initial error state sliding function equal to zero.

  • PDF

Study on Analyzing and Correction of Dynamic Battery Alignment Error in Naval Gun Fire Control System by using Image of Boresight Telescope (포배열카메라 영상을 활용한 함포 사격통제시스템의 동적배열오차 분석 및 보정방법)

  • Kim, Eui-Jin;Suh, Tae Il
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.16 no.6
    • /
    • pp.745-751
    • /
    • 2013
  • In naval gun firing, firing accuracy comes from the combination of each component's accuracy in CFCS (Command and Fire Control System) like tracking sensors and gun. Generally, battery alignment is done to correct the error between gun and tracking sensor by using boresight telescope on harbor and sea. But normally, the battery alignment can compensate only the static alignment error and ignore dynamic alignment error which is caused by own ship movement. There was no research on this dynamic alignment error until now. We propose a new way to analyze dynamic arrangement error by using image of boresight telescope. In case of the dynamic alignment error was due to time delay of own ship attitude information, we propose the way to compensate it.

A Study on Reducing Profile Error of Multi Spindle Control in NC Machine Tools (NC 공작기계(工作機械) 동시다축제어(同時多軸制御)에서의 오차 저감)

  • Park, Jong-Bong
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.3 no.2
    • /
    • pp.115-121
    • /
    • 2000
  • This paper presents reducing method of profile error on a mechanical tuning for multi-spindle control of NC machine tools. To reduce the profile error in the feed drive system, it is useful to adopt same transfer function of multi spindle machine tools. By selecting the correction vector of servo rigidity and natural vibration on JK map, multi spindle control can be tuned by mechanical parameters with small profile error.

  • PDF

Position-type fuzzy controller using the accumulated error scaling factor (누적오차 조정계수를 이용한 위치형 퍼지제어기)

  • 김동하;전해진;최봉열
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.177-177
    • /
    • 2000
  • In this paper, we propose a two-input two-output fuzzy controller to improve the performance of transient response and to eliminate the steady state error. The outputs of this controller are the control input calculated by position-type fuzzy controller and the accumulated error scaling factor. Here, the accumulated error scaling factor is adjusted on-line by fuzzy rules according to the current trend of the controlled process. To show the usefulness of the proposed controller, it is applied to several systems that are difficult to get satisfactory response by conventional PD controllers or PI controllers.

  • PDF

Efficient Error Management Method in Process Control System Described by SFC Graphical Language (SFC 그래픽 언어로 기술된 공정제어 시스템에서 효율적인 에러관리 방법)

  • 전호익;우광준
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
    • /
    • v.14 no.1
    • /
    • pp.59-66
    • /
    • 2000
  • As the highly complex and precise control functions are required in modern industrial process control system, the complex function models and developed in each hardware and software of PLC. The SFC graphical language is very powerful for describing the sequential logic control algorithm, on the other hand it graphical language is very powerful for describing the sequential logic control algorithm, on the other hand it has problems in describing the interlock logic control algorithm, such as error management algorithm. In this paper, we propose the efficient error management method using the action qualifiers to design the error management algorithm in industrial process control system described scheme, we realize the error management logic in process control system of film coating machine.From the experiment results, we confirm that the proposed scheme is very useful in aspects to realize easily th error management logic and to reduce the memory capacity for user's program.

  • PDF

Compensation of Geometric Error by the Correction of Control Surface (제어곡면 수정에 의한 기하오차 보정)

  • Ko, Tae-Jo;Park, Sang-Shin;Kim, Hee-Sool
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.18 no.4
    • /
    • pp.97-103
    • /
    • 2001
  • Accuracy of a machined part is determined by the relative motion between the cutting tool and the workpiece. One of the important factors which affects the relative motion is the geometric errors of a machine tool. In this study, firstly, geometric errors are measured by laser interferometer, and the positioning error of each control point selected uniformly on the control surface CAD model can be estimated from th oirm shaping model and geometric error data base. Where a form shaping function is derived from the link of homogeneous transformation matrix. Secondly, control points are shifted to the estimated amount of positioning errors. A new control surface is modeled with NURBS(Non Uniform Rational B-Spline) surface approximation to the shifted control points. By generating tool paths to the redesigned control surface, we reduce the machining error quite.

  • PDF