• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.96.3-96
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• 2002

A scheme of clarifying fault feature in the residual is given for model-based fault detection and diagnosis of control systems. It is based on the residual generation using a robust filter and the noise suppresion in test statistics of the residual by multi-scale discrete wavelet transform. By clarifying the fault feature in the residual, the difficulties of existing model based approaches via adopting a threshold can be overcomed and it has advantage of taking the false alarm and missed detection into acount at the same time, which can make the fault detection and diagnosis easy and correct. To show the effectiveness of our approach, the simulation results are illustrated for a linear syste...

• Proceedings of the Korean Nuclear Society Conference
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• 1997.10a
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• pp.443-448
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• 1997

The intelligent software system for nuclear power plants (NPPs) has been conceptually designed in this study. Its design goals are to operate NPPs in n improved manner and to support operators' cognitive tasks. It consists of six major modules such as "Information Processing," "Alarm Processing," "Procedure Tracking," "Performance Diagnosis," and "Event Diagnosis" modules for operators and "Malfunction Diagnosis" module for maintenance personnel. Most of the modules have been developed for several years and the others are under development. After the completion of development, they will be combined into one system that would be main parts of advanced control rooms in NPPs. that would be main parts of advanced control rooms in NPPs.

• Journal of Electrical Engineering and Technology
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• v.1 no.1
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• pp.28-34
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• 2006

Recently, in accordance with the development of IT technology, it is prevalent for power quality monitors to be connected to each other via networks and share their data because such networks provide system-wide insights to customers concerning power quality. Those systems can alarm and display power quality events for the convenience of customers. However, if a power quality event occurs, it is difficult for customers to determine its cause and solution because the systems do not provide appropriate power quality diagnosis functions. The power quality management system presented in this paper has been developed to provide customers with various power quality diagnosis functions so that they can cope well with power quality problems with the right measure in the right place. This paper presents the structure and functions of the developed power quality management system and shows some results of the power diagnosis functions.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.21 no.4
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• pp.264-270
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• 2018

Purpose: The aim of this study was to describe functional gastrointestinal disorders (FGID) presented in a tertiary medical center, characteristics of patients and results of the diagnostic work-up together with an outcome during the follow up. Methods: This was a retrospective, single center, observational study including all patients who were diagnosed with FGID based on Rome III criteria from January to December 2015 in tertiary medical center. Results: Overall 294 children were included (mean age, 8.9 years [range, 1-18 years]; 165 females). Majority had functional constipation (35.4%), followed by functional abdominal pain (30.6%), irritable bowel syndrome (17.0%), functional dyspepsia (12.6%), functional nausea (3.4%) and abdominal migraine (1.0%). Regression model found that only significant factor associated with improvement of symptoms is the establishment of the functional diagnosis at the first visit (hazard ratio, 2.163; 95% confidence inverval, 1.029-4.544). There was no association between improvement of symptoms and presence of alarm signs/symptoms (weight loss, nocturnal symptoms and severe vomiting) at diagnosis. Furthermore, in pain symptoms (functional abdominal pain, irritable bowel syndrome, dyspepsia) no treatment positively correlated with pain improvement. Conclusion: Regardless of the initial diagnosis of FGID, positive diagnosis at the first visit increases a chance for resolution of symptoms.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.10
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• pp.717-727
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• 2022

An algorithm is realized for estimating the component fault and health diagnosis such as a deterioration. Based on the turbofan engine health diagnosis model, from the health parameters which are estimated by a real time tracking filter, the outliers are eliminated efficiently by an effective median filter to minimize an false alarm. The difference between the fault and deterioration trends is identified by the detection measure for abrupt change, thereby the clear diagnosis classifying the fault and the health condition is possible. The effectiveness of the algorithm for fault and health diagnosis is verified from the simulated results of engine component faults and deterioration.

• Proceedings of the Korean Nuclear Society Conference
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• 1998.05a
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• pp.329-334
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• 1998

원자력발전소와 같이 복잡하고 안전성이 강조되는 경보처리 및 표시계통은 개발개념의 적합성 (설계요건의 타당성), 적용된 알고리즘의 완결성(지식기반과 소프트웨어의 확인)과 인간공학적 유용성의 평가가 상당히 중요하다. 동적 경보계통(Alarm and Diagnosis-Integrated Operator Support System : ADIOS)은 다음과 같은 실험을 통해 경보처리 알고리즘의 완결성과 인간공학적 유용성을 확인하였다.·예비기능시험(Preliminary functional test)·Petri net 을 이용한 알고리즘의 완결성 확인(Verification)·전규모 시뮬레이션 환경에서의 인간공학적 성능평가(Validation and Evaluation)

• Journal of Advanced Marine Engineering and Technology
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• v.38 no.6
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• pp.744-750
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• 2014

The monitoring and abnormality warning of marine diesel engine are important to take appropriate responses for safety navigation. If maintenance engineers do not take appropriate response because of diagnosis mistakes, it will occur a nasty accident. Therefore, we need integrated monitoring and diagnosis system for supporting a diagnosis objectively. In this paper, we analyze time-series data which measured by real-time, monitor the changing of conditions and trends of the analyzed data. Furthermore, we design and implement a monitoring and diagnosis system for objective supporting of real-time diagnosis. When the integrated monitoring and diagnosis system is adopted, it can help to improve stability of marine diesel engine by providing abnormality warning alarm with appropriate responses.

• Journal of KSNVE
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• v.6 no.3
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• pp.325-332
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• 1996

One of the greatest shortcoming in today's predictive maintenance program is the ability to diagnose the mechanical and electrical problems within the machine when the vibration exceeds preset overall and spectral alarm levels. In this study, auto-diagnosis system is constructed by using A/D converter to convert analog to digital singal. With this device the system analyses input signal to diagonosis machine condition. Many plots, which display machine condition, and input values of every channel are calculated in this system. If the falut is found, the system diagnoses automatically using fuzzy algorithm and trend monitoring. Prediction is also performed by the grey system theory. Operator finds out eh machine operating condition intuitively based on with personal computer CRT in using this system.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2590-2593
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• 1999

This paper describes the development of Emergency Generator Equipments Diagnosis System for monitoring generator equipments and battery system. This system is capable of measuring on up to 20 separate sites of generator, engine and periphral equipment's. Battery system also capable of measure the setting time, float and discharge voltage of up to 240 cells in a single installation, and has the memory capacity to store battery's alarm data information on up to 200 separate sites. This system are easy to maintain and attain cost effectively, so that prepared for meeting the customer's service needs immediately. The system is additionally programmed with a each model, that will enable to accurately determine the generator equipments and remain battery capacity in a system following a short discharge test. It is also equipped with remote interrogation and control facilities.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.172-175
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• 2003

The enterprise find a solution to the problems such as a reduction of manufacturing period, accurate analysis for customer demand, improvement for customer service and rise of manufacture accomplishment. Internet is a good solution to such problems. Internet offers WWW(World Wide Web), remote control, file transfer and e-mail service. Among the services, WWW takes large portion because of convenient GUI, easy information search and unlimited information registration. Remote Monitoring Server(RMS) system that uses network service is constructed for chip mounter. Hardware base consists of RMS, chip mounter and C/S(Customer Service) server. Software includes DBMS and various modules in server home page. This provide product number, bad product number, trouble code, content and countermeasure in real-time information module, user information in setup module, detailed error information in fault diagnosis module, fault history in fault history module and customer information in customer service management module.