• Title/Summary/Keyword: diagnose

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A Study on the Fault Diagnosis of Roller-Shape Using Frequency-Domain Analysis of Tension Signals (장력신호의 주파수 해석을 이용한 롤 형상 이상 진단에 관한 연구)

  • Sin, Gi-Hyeon
    • Journal of the Korean Society for Precision Engineering
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    • v.17 no.12
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    • pp.107-114
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    • 2000
  • Rollers and rolls in the continuous process systems are noes of key components that determine the quality of web products. The condition of rollers and rolls(ex. eccentricity wear) should be consistently monitored in order to maintain the process conditions (ex. tension, edge position) within a required specification. In this paper, a new diagnosis technique is suggested to detect the defect of rollers/rolls (ex. eccentricity, wear) based on frequency domain analysis of web tension signal. The kernel of this technique is to use the spectrum amplitude of tension signal which allows to identify the fault rollers/rolls and to also diagnose the degree of fault in corresponding rollers and rolls. The experimental results proved that the suggested diagnosis technique can be successfully used to identify the defect rollers and rolls as well as to diagnose the degree of the defect of those rollers. The suggested technique can be applied to monitor and diagnose the shape of rollers and rolls in various multi-span web transport systems.

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Development of an Expert System (ESRCP) for Failure Diagnosis of Reactor Coolant Pumps (원자로냉각재펌프 고장진단을 위한 전문가시스템의 개발)

  • Cheon, Se-Woo;Chang, Soon-Heung
    • Nuclear Engineering and Technology
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    • v.22 no.2
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    • pp.128-138
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    • 1990
  • This paper presents a prototype expert system (ESRCP) for Reactor Coolant Pumps. The purpose of this system is to diagnose RCP failures and to offer corrective operational guides to plant operators. The first symptoms for the diagnosis are the alarms which are related to the RCP domain. Alarm processing is required to find a primary causal alarm when multiple alarms occur. The system performs the alarm processing by rule-based deduction or priority factor operation. To diagnose the RCP failure, the system performs rule-based deduction or Bayesian inference. Various sensor readings are required as symptoms to infer a root cause. When the symptoms are insufficient or uncertain to diagnose accurately, Bayesian inference is performed.

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Instantaneous Frequency Estimation of the Gaussian Enveloped Linear Chirp Signal for Localizing the Faults of the Instrumental Cable in Nuclear Power Plant (가우시안 포락선 선형 첩 신호의 순시 주파수 추정을 통한 원전 내 계측 케이블의 고장점 진단 연구)

  • Lee, Chun Ku;Park, Jin Bae;Yoon, Tae Sung
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.7
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    • pp.987-993
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    • 2013
  • Integrity of the control and instrumental cables in nuclear power plant is important to maintain the stability of the nuclear power plants. In order to diagnose the integrity of the cables, the diagnostic methods based on reflectometry have been studied. The reflectometry is a non-destructive method and it is applicable to diagnose the live cables. We introduce a Gaussian enveloped linear chirp reflectometry to diagnose the cables in the nuclear power plants. In this paper, we estimate the instantaneous frequency of the Gaussian enveloped linear chirp signal by using the weighted robust least squares filtering to localize the impedance discontinuities in the class 1E instrumental cable.

Unusual Necrotizing Uterine Adenocarcinoma in a Dog

  • Kim, Tae-Jung;Shin, Sung-Shik;Park, Sang-Ik
    • Journal of Embryo Transfer
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    • v.32 no.4
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    • pp.325-329
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    • 2017
  • A 2-year-old female Maltese dog was admitted with a history of pyometra and resulting peritonitis and septicemia. Uterine specimen sampled by ovariohysterectomy was processed routinely for histopathological observation. Grossly, the uterine mucosa was covered with necrotic debris and on the cut surface, lesion extended into the uterine wall. Microscopically, severe necrosis was observed throughout thickened mucosa, submucosa, and wall of uterus. Tumorous lesions composed of anaplastic cells with bizarre nuclei or tubular structures of cuboidal to short columnar cells were infrequently observed around the necrotic lesions and muscular layer far from necrotic areas. Immunohistochemically, central necrotic area with ambiguous cell and tissue structures, peri-necrotic tumor lesions, and muscular layer were strongly positive for cytokeratin. Since huge necrosis of adenocarcinoma lesions in this case made it difficult to diagnose, immunohistochemical results enable to diagnose as a severe necrotizing adenocarcinoma. Thus, histopathological and immunohistochemical findings in this case may serve as an important knowledge to diagnose uterine adenocarcinoma with huge necrosis in the veterinary field.

Electrical Characteristics of ZnO Blocks by a Lightning Impulse Current and the Expert System to Diagnose Arrester Deterioration (뇌충격전류에 의한 산화아연형 피뢰기 소자의 전기적 특성과 피뢰기 열화진단 전문가 시스템)

  • Gil, Gyeong-Seok;Han, Ju-Seop;Song, Jae-Yong;Kim, Myeong-Jin;Kim, Jeong-Bae;Jo, Han-Gu
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.51 no.4
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    • pp.152-157
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    • 2002
  • This paper describes an effect of a single- and a quadruple-lightning impulse currents on electrical characteristics of ZnO blocks, and an expert system to diagnose arrestor deterioration. To deduce the parameters needed for diagnosing arrester deterioration, an accelerate deterioration teat is carried out. In the experiment, leakage current components are measured. Also, wave height distribution of the leakage current according to the progress of arrester deterioration is analyzed. From the experimental results, the wave height distribution of the leakage current showed conspicuous difference even in an immaterial leakage current increase. Therefore, the use of wave height distribution of the leakage current in deterioration diagnostic technique makes more accurate diagnosis than the conventional method by using only a leakage currant value. Finally, the expert system based on the experimental results is developed and the system can diagnose arrestor deterioration by measuring the leakage current and its wade height distribution.

A Study on a Control Model for the Diagnostic and Nonconformity Rate in an Instrumental Process Involving Autocorrelation (자기상관이 있는 장치산업에서 공정 진단 및 부적합품률 제어모형에 관한 연구)

  • Koo, Ja-Hwal;Cho, Jin-Hyung
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.33 no.1
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    • pp.33-40
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    • 2010
  • Because sampling interval for data collection tends to be short compared with the overall processing time, in chemical process, instrumental process related tanks or furnace collected data have a significant autocorrelation. Insufficient control technique and frequent control actions cause unstable condition of the process. Traditional control charts which were developed based on iid (independently and identically distributed) among data cannot be applied on the existence of autocorrelation. Also unstable process is difficult to identity or diagnose. Because large-scale process has a lot of measurable variables and multi-step-structures among data, it is difficult to find relation between measurable variables and nonconformity. In this paper, we suggested an appicable model to diagnose the process and to find relation between measurable variables (CTQ) and nonconformity in the process having autocorrelation, unstable condition frequently, a lot of measurable variables, and multi-step-structure. And we applied this model to real process, to verify that the process engineers could easily and effectively diagnose the process and control the nonconformity.

Diagnosis of Medium Voltage Cables for Nuclear Power Plant

  • Ha, Che-Wung;Lee, Do Hwan
    • Journal of Electrical Engineering and Technology
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    • v.9 no.4
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    • pp.1369-1374
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    • 2014
  • Most accidents of medium-voltage cables installed in nuclear power plants result from the initial defect of internal insulators or the initial failure due to poor construction. However, as the service years of plants increase, the possibility of cable accidents is also rapidly increases. This is primarily caused by electric, mechanical, thermal, and radiation stresses. Recently, much attention is paid to the study of cable diagnoses. To date, partial discharge and Tan${\delta}$ measurements are known as reliable methods to diagnose the aging of medium-voltage cables. High frequency partial discharge measurement techniques have been widely used to diagnose cables in transmission and distribution systems. However, the on-line high frequency partial discharge technique has not been used in the nuclear power plants because of the plant shutdown risk, degraded measurement sensitivity, and application problems. In this paper, the partial discharge measurement with a portable device was tried to evaluate the integrity of the 4.16kV and 13.8kV cable lines. The test results show that the high detection sensitivity can be achieved by the high frequency partial discharge technique. The present technique is highly attractive to diagnose medium voltage cables in nuclear power plants.

Effective Harmonic Diagnose Tool for Power Quality Problems (전기품질개선을 위한 효율적인 고조파 진단 툴 개발)

  • 설용태;이의용
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.3 no.1
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    • pp.63-68
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    • 2002
  • In this paper harmonic diagnose tool is described for electric evaluate the power quality at industrial power systems is described both simulation and experimental testing during various operation conditions. PTW (Power Tools for Windows) and harmonic measuring instrument are organized around personal computer and/or instrumentation study environments interconnected via RS-232. Unknown zero sequence impedance data of cable is calculated by the modified T&D and BICC method. IEEE standard is also used to estimate the transformer input data. the proposed system provides a flexible and effective environment to diagnose the power quality at industrial distribution systems by utilizing simulations and actual field data.

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Information Systems for Organizational Agility: Action Research on Resource Scheduling at the Universidad de Chile

  • Seo, Dong Back;La Paz, Ariel I.;Miranda, Jaime
    • Asia pacific journal of information systems
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    • v.24 no.4
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    • pp.417-441
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    • 2014
  • Organizations need to exhibit characteristics of agility to stay ahead of their competitors and to survive in dynamic environments. One major concern for organizations is how to implement Information Systems (ISs) to enhance their agility. Organizations tend to spend too many resources to change their entire IS instead of only the components that cause problems without exactly knowing whether it enables or suppress organizational agility. To address these shortcomings and practical issues, we provide a framework to assess organizational agility and to diagnose a problem related to IS. By applying this prototype of the Agility Framework, we were able to diagnose a problem that the department of Management Control and Information Systems at the Universidad de Chile had and planned actions for them to improve its organizational agility with a course scheduling system, eClasSkeduler. This action research, which took more than 25-month for the first cycle, further develops the Agility Framework, which not only provides a way to link IS with organizational functions but also illustrates how to use it to diagnose a situation and plan actions for improving organizational agility through an information system.

A Study for Diagnostic Correspondent Rates between DSOM and Korean Medical Doctors' Diagnosis about Menstrual Pain (월경통 환자에 대한 한방진단시스템의 진단일치도 연구)

  • Lee, In-Seon;Cho, Hye-Sook;Ji, Gyu-Yong;Lee, Yong-Tae;Kim, Jong-Won;Jeon, Soo-Hyung;Kim, Gyeong-Min;Kim, Gyeong-Cheol;Ki, Kyu-Kon
    • The Journal of Korean Obstetrics and Gynecology
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    • v.28 no.3
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    • pp.1-10
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    • 2015
  • Objectives Diagnosis System of Oriental Medicine (DSOM) was made as a computerized assistant program for oriental medicine doctors to be able to diagnose with statistical basis. Then DSOM uses questionnaires filled out by respondents with explanatory guide. But if the respondents misunderstand the meaning of the passages, the results were quite the opposite. Methods This study was designed to investigate the diagnostic correspondent rates between DSOM and TKM practitioners. First, let the respondents answer to DSOM. After that, three doctors diagnosed the respondents and marked 'p' when they diagnose that the respondent had the pathogenic factors, marked 'n' when they diagnose that the respondent had the pathogenic factors but not severs, and did not marked when they diagnose that the respondent didn't have the pathogenic factors. Finally, this study was investigated the correspondent rates of diagnosis between DSOM and doctors. Results In the pathogenic factor of three including insufficiency of Yin (陰虛), the correspondent rates were 90%. In the pathogenic factor of nine including deficiency of qi (氣虛), the correspondent rates were 80%. In the pathogenic factor of four including blood stasis (血瘀), the correspondent rates were 70%. In HH and HL, they showed the correspondent rates of 61.77%. The correspondent rate of heat (熱) was highest (96.88%). The correspondent rate of insufficiency of Yang (陽虛) was lowest (0%). In LH and LL, they showed the correspondent rates of 88.31%. The correspondent rate of blood stasis (血瘀) was lowest (71.76%). They all showed the correspondent rates of over 70%. Conclusions In DSOM and Doctors' diagnose, they showed the correspondent rates of 83.60%.