• Title/Summary/Keyword: Parity

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Fault Detection and Isolation System for DC motor driven Centrifugal Pump-Pipe Systems: Parity Relation Approach (직류전동기 구동 원심펌프-파이프 계통의 고장검출진단시스템: 등가관계 접근법)

  • Park, Tae-Geon;Ryu, Ji-Su;Lee, Kee-Sang
    • Proceedings of the KIEE Conference
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    • 1998.07b
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    • pp.819-821
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    • 1998
  • This paper deals with a method or a residual generation for fault isolation in a centrifugal pump with a water circulation system, driven by a speed controlled dc motor. It is based on parity relations derived from the moving-average model of the system and is used to identify sensor faults and two possible brush and impeller faults, where the former is dealt with additive faults, while the latter characterized as discrepancies between the nominal and actual plant parameters of the system is modelled by multiplicative faults. We will represent the propagation of this uncertainty to the model matrices by the approximate handling of partial derivatives of polynomials. With multiplicative faults, the transformation matrix implemented in the residual generator are calculated on-line. The simulation studies demonstrate that small changes of the system can be detected and diagnosed by using the method.

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A PARITY SPACE APPROACH TO FAULT DETECTION FOR A POSITION SERVO SYSTEM (패리티 공간기법을 이용한 위치 서보계의 고장검출)

  • Choi, Kyung-Yung;Park, Tae-Geon;Lee, Kee-Sang
    • Proceedings of the KIEE Conference
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    • 1997.07b
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    • pp.746-748
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    • 1997
  • The parity relation approach for the fault detection and isolation (FDI) of a large diesel engine actuator position servo system is presented. Main purpose of the FDI system is to detect and isolate two important faults, actuator fault and sensor fault, that, if not detected and compensated, degrade the overall system performance. Simulation results are given to show the practical applicability of the FDI scheme.

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Automatic detection of the lung orientation in digital PA chest radiographs

  • Nahm, Kie-B.
    • Journal of the Optical Society of Korea
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    • v.1 no.1
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    • pp.60-64
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    • 1997
  • An image processing algorithm is presented that can identify the orientation as well as the left/right side (parity) of the digitized radiographs. The orientation was found by computing the mean square deviation between the sampled gray values along the center and their best-fit linear regression relations. The parity was determined by comparing the area difference between two thresholded images of the left and the right side around the heart, which is assumed to be around the center of the image. This method was tested with 86 images with their orientations intentionally rotated. The rotation was limited to multiples of 90 degrees, as this was the way the rotation is most likely to happen in the clinical environment. We obtained positive responses for 85 out of 86 images subject to the screening.

A Fault Tolerant Control for Distributed Programmable Logic Controller System (분산형 PLC 시스템에서의 고장 허용 제어)

  • Jeong, S.K.;Jeong, Y.M.
    • Journal of Power System Engineering
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    • v.8 no.1
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    • pp.62-68
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    • 2004
  • This paper describes a fault tolerant control in distributed PLC(Programmable Logic Controller) system to ensure reliability of controllers which have some faults simultaneously. First, the behavior of PLC is modeled as discrete expressions using Galois field. Then, we design the control laws for additional spare controllers to generate parity code with two dimensions. Finally, the algorithm for estimating normal output instead of abnormal output from the controllers with fault is suggested. Comparing to the traditional duplication method, the suggested method can reduce the number of spare controllers significantly to ensure control reliability. This method will be applied to an automatic system in order to increase reliability. Also, it can improve cost performance of the system.

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Case Report of Post-CVA Voiding Dysfunction Treated with Gamidaejihwang-tangaggam (중풍 환자의 배뇨장애에 대한 가미대지황탕가감 치료 증례보고)

  • Hong, Sang-Hoon;Park, Sang-Eun
    • Herbal Formula Science
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    • v.23 no.2
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    • pp.261-269
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    • 2015
  • Objectives : The purpose of this case reports is to report the possibility of Post-CVA voiding dysfunction treated with Gamidaejihwang-tangaggam(加味大地黃湯加減). Methods : Three patients with Post-CVA voiding dysfunction were treated by Gamidaejihwang-tanggagam. Effect of treatment is assessed as Bladder Function Parity. Results and conclusions : Bladder function parity score improved, in three case. Additional research is needed on the effects of Gamidaejihwang-tanggagam for a Post-CVA Voiding disfunction.

Efficient Implementation of RAID Level 5 on Single Disk I/O (SDIO에서 RAID 레벨 5의 효율적인 구현)

  • 김호진;황인철;맹승렬;윤현수
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.64-66
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    • 2004
  • 단일 입출력 디스크(SDIO)는 클러스터 환경에서 빠르고 신뢰성 있는 분산 저장장치를 제공한다. 단일 입출력 디스크는 주로 RAID 레벨 0이나 레벨 1을 사용하는데, RAID 레벨 5를 사용함으로써 좋은 성능과 좋은 신뢰도 그리고 높은 디스크 용량 사용률을 얻을 수 있다. 그러나 RAID 레벨 5를 사용함으로써 네트웍 오버헤드 문제, 작은 데이터의 기록 성능 문제, 동시 기록 문제가 발생한다. 위의 새 가지 문제를 해결하거나 최소화하기 위하여 본 논문에서는 Parity Cumulating이라는 접근방법을 제시한다. Parity Cumulating은 패리티의 계산을 두 개의 노드로 분산시킴으로써 네트웍 오버헤드를 줄이고, 패리티를 버퍼에 저장하고 디스크에 작업이 없을 때 처리함으로써 작은 데이터의 기록 성능을 높이며 동시 기록시 일관성을 지킨다.

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Analysis a LDPC code in the VDSL system (VDSL 시스템에서의 LDPC 코드 연구)

  • Joh, Kyung-Hyun;Kang, Hee-Hoon;Yi, Sang-Hoi;Na, Kuk-Hwan
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.999-1000
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    • 2006
  • The LDPC Code is focusing a powerful FEC(Forward Error Correction) codes for 4G Mobile Communication system. LDPC codes are used minimizing channel errors by modeling AWGN Channel as VDSL system. The performance of LDPC code is better than that of turbo code in long code word on iterative decoding algorithm. LDPC code are encoded by sparse parity check matrix. there are decoding algorithms for a LDPC code, Bit Flipping, Message passing, Sum-Product. Because LDPC Codes use low density parity bit, mathematical complexity is low and relating processing time becomes shorten.

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An Effective Quality Estimation in Pixel-domain Distributed Video Coding (화소영역 분산비디오 부호화기법에서 효과적인 화질 예측방법)

  • Kim, Jin-soo
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.10a
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    • pp.1024-1026
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    • 2013
  • DVC (Distributed Video Coding) techniques provides a basic theory for the implementation of low-power video encoder. Conventional methods decide the parity bit request at decoder side. These are effective in controlling the bit-rate, but, are not able to control the visual quality. Thus, this paper presents an effective method of estimating visual quality improved by correcting the virtual channel noise for the reconstructed frame. Through several experiments, it is shown that the proposed method are able to estimate effectively the decoded visual quality.

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Cycles in Conditional Faulty Enhanced Hypercube Networks

  • Liu, Min;Liu, Hongmei
    • Journal of Communications and Networks
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    • v.14 no.2
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    • pp.213-221
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    • 2012
  • The architecture of an interconnection network is usually represented by a graph, and a graph G is bipancyclic if it contains a cycle for every even length from 4 to ${\mid}V(G){\mid}$. In this article, we analyze the conditional edge-fault-tolerant properties of an enhanced hypercube, which is an attractive variant of a hypercube that can be obtained by adding some complementary edges. For any n-dimensional enhanced hypercube with at most (2n-3) faulty edges in which each vertex is incident with at least two fault-free edges, we showed that there exists a fault-free cycle for every even length from 4 to $2^n$ when n($n{\geq}3$) and k have the same parity. We also show that a fault-free cycle for every odd length exists from n-k+2 to $2^n-1$ when n($n{\geq}2$) and k have the different parity.

Construction of Semi-Algebra Low Density Parity Check Codes for Parallel Array Processing (병렬 어레이 프로세싱을 위한 반집합 대수 LDPC 부호의 구성)

  • Lee Kwang-jae;Lee Moon-ho;Lee Dong-min
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.30 no.1C
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    • pp.1-8
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    • 2005
  • In this paper, we present a novel LDPC code construction called as semi-algebra low density parity check(LDPC) codes which is one kind of deterministic LDPC code based on dual-diagonal sub-matrix. The constructing method results in a class of high rate LDPC codes. Codes in this class have a large girth and good minimum distances. Furthermore, they can be implemented by simple parallel array architecture using cyclic shift register and perform well with the iterative decoding.