• 한국정밀공학회지
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• 제17권12호
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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.

• Nuclear Engineering and Technology
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• 제22권2호
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• pp.128-138
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• 1990

본 논문에서는 원자로냉각재펌프 고장진단 전문가시스템 (ESRCP)에 대해 기술하였다. 이 시스템의 목적은 RCP의 고장진단과 함께 발전소 운전원에게 적절한 운전 조작 및 비상조치 사항 등을 알려주는데 있다. 진단을 위한 일차적 증상은 RCP 영역에 관련된 경보들이다. 경보처리는 Rule-based Deduction 또는 Priority Factor Operation에 의한다. 고장진단은 Rule-based Deduction이나 Bayesian Inference에 의해 수행된다. 각종 Sensor들의 측정값들은 정확한 원인을 진단하기 위해 필요로 하다 증상들이 부족하거나 불착실성을 나타낼 때는 Bayesian Inference로 고장을 진단한다.

• 전기학회논문지
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• 제62권7호
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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.

• 한국수정란이식학회지
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• 제32권4호
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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.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제51권4호
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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.

• 산업경영시스템학회지
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• 제33권1호
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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.

• Journal of Electrical Engineering and Technology
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• 제9권4호
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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.

• 한국산학기술학회논문지
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• 제3권1호
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• pp.63-68
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• 2002

본 연구는 산업용 전력계통에서의 전기 품질을 개선하기 위한 고조파 진단 툴의 개발에 대한 것이다. 이 시스템은 계통의 다양한 운전상태에서 시뮬레이션과 계측을 통한 전기품질 분석에 적합하도록 구성하였다. 시뮬레이션은 PTW(Power Tools for Windows)를 이용하였고, 고조파 측정에는 Dranetz사의 PP-4300 장비가 RS-232를 통해 개인용 컴퓨터와 연결되어 시뮬레이션과 실측 데이터를 비교분석 할 수 있게 하였다. 케이블의 영상분 임피던스 등 미진한 입력자료는 수정된 T&D와 BICC를 이용하였고, IEEE표준 데이터가 변압기 입력자료 측정에 적용되었다. 제안된 시스템은 대규모 실제 산업용 수변전 계통에 적용한 결과 고조파 진단의 유연성과 효율성을 입증할수 있었다.

• Asia pacific journal of information systems
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• 제24권4호
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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.

• 대한한방부인과학회지
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• 제28권3호
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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%.