• Journal of Intelligence and Information Systems
• /
• v.2 no.1
• /
• pp.11-26
• /
• 1996

본 논문에서는 화학공정의 이상 진단을 위한 지식 기반 조업 지원 시스템의 개발에 관하여 살펴보고자 한다. 조업지원 시스템에서 가장 핵심적인 부분은 공정에 비정상 상황이 발생한 경우 이를 감지하고, 공정에 발생한 증상들을 분석하여 이상의 근본 원인을 찾아내는 작업-이상 진단이다. 이상 진단을 효과적으로 수행하기 위해서는 적절한 데이터의 해석이 매우 중요한데, 기존의 데이터 해석법들은 정상상태에 기반한 방법들을 동적거동을 효과적으로 표현하기에는 어려움이 많다. 본 연구에서는 RBF에 기반한 신경망을 사용하여 동적을 효과적으로 표현할 수 있는 정성적인 데이터 해석 모듈을 구축하였으며, 이 모듈에서는 공정에서 측정된 정략적인 센서값들을 정성적인 정보로 가공하여 이상진단 모듈에 제공한다. 본 연구에서는 효과적인 이상진단을 위하여 기존의 인과관계 그래프 모델(Cause Effect DiGraph)에 기반한 두가지 그래프 모델을 개발하였다. RCED(Reduced Caue Effect Digraph)는 공정의 측정 변수만으로 공정의 인과관계를 표현하는 오프라인으로 구축된 지식베이스 모델이며, PGTT(Pattern Graph Through Time)는 공정에서 발생한 증상간의 인과관계를 실시간으로 나타내는 동적인 모델이다. 이상, 신경망에 기반한 정성적인 데이터 해석 모듈과 이상진단 모듈을 전문가 시스템 도구인 G2를 DEC AlphaStation 상에서 폴리프로필렌 공정에 대한 조업지원전문가 시스템을 구축하고 이를 적용하여보았다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2006.05a
• /
• pp.218-221
• /
• 2006

High reliability and minimization of operating cost are important problems for both engine-manufacturer and user in operation of gas-turbine engine, for which various performance diagnostics including a fault identification have been a major issue nowadays. Performance estimation in the off-design conditions, however, encounters problems of large errors and of poor convergence because of much required data to be evaluated. In this study, a diagnostics code of engine performance has been developed by using GPA(Gas Path Analysis). Quantitative performance deterioration of the turbo-shaft engine for SUAV has been estimated with altitude variation and is compared with that obtained by GSP code.

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.16 no.5 s.110
• /
• pp.495-502
• /
• 2006

A fault diagnosis method is developed in this study using automaton through quantization of vibration signals for normal and faulty conditions, respectively. Automaton is a kind of qualitative model which describes the system behaviour at the level of abstraction. The system behavior was extracted from the probability of the output sequence of vibration signals. The sequence was made as vibration levels by reconstructing the originally measured vibration signals. As an example, a fault diagnosis for the bearing of ATM machine was done, which detected the bearing fault with confident level compared to any other existing methods of kurtosis or spectrum analysis.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.279-284
• /
• 2005

Knowledge based fault diagnosis has a limitation in determining the cause and scheme for the fault, because it detects faults from signal pattern only Therefore, model-based fault diagnosis is requested to determine the fault by analyzing output of the equipment from its dynamic model. This research shows a method how to devise the automaton of system as a model for normal and faulty condition through the reduction of handling data by quantization of vibration signals and the example which is concerning to the bearing of ATM. The developed model based fault diagnosis was applied to detect the faulty bearing of ATM, which results.

• Journal of the Korean Arthroscopy Society
• /
• v.10 no.2
• /
• pp.135-140
• /
• 2006

Diagnosis and treatment of the unstable shoulder is one of the more difficult problems in orthopaedic surgery. There is confusion between the normal laxity with translation and subluxation of the humeral head relative to the glenoid and an abnormal amount of laxity, leading to pain and dysfunction. Unfortunately, there is no single treatment that applied to all lesions that cause the instability. It is imperative, therefore, that an accurate diagnosis be made, including the directions and degree of shoulder instability as well as any coexisting problems. Anatomical defects must be defined. Common factors that could most readily compromised instability repair are examined. These include techniques for making an accurate diagnosis with identification of the precise anatomical pathology, and the rationale for appropriate surgical treatment with the avoidance of technical complication such as unnecessary hardware or exposures that might lead to residual instability, arthritis, and nerve or vascular injuries. Additional injuries may be prevented by careful rehabilitation postoperatively to restore shoulder stability, flexibility, and endurance prior to an individual's return to stressful sports or work.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.31 no.5D
• /
• pp.679-687
• /
• 2011

Implementation of semi-public management system of intra-city bus achieve excellent results but there are some side effects like increase of the fatal traffic accidents. This study tries to develop decision making model of measures of reducing traffic accidents following implementation of semi-public management system of intra-city bus. And survey with traffic experts and analytic hierarchy process are used for data survey and analysis. Quantitative measures and qualitative measures are suggested as high assessment items of AHP. Quantitative measures of low assessment items composed of a raise in the number of bus and safety device installation, facility supplement of bus stop, supplement of pedestrian protection facility, traffic safety assessment and supplement. Qualitative measures composed of system organization, redesign bus route, reinforcement of education, campaign and enforcement. The results of this study are as follows. First, the result turns out more weights are calculated on quantitative measures than on qualitative measures. Second, It is turned out in order of facility supplement of bus stop and traffic safety assessment and supplement as the quantitative measures. Third, as qualitative measures, system organization and redesign bus route are in the order. The results of this study are considered to be a basic data which can be referred if measures on the decrease of traffic accident are established and implemented in other cities and provinces.

• Journal of fish pathology
• /
• v.12 no.1
• /
• pp.24-31
• /
• 1999

Optimization and standardization of solid phase enzyme immunoassay were done for the diagnosis of edwardsiellosis in fish. The analyzed degree of immobilized antibody on surface of solid phase with peroxidase saturation method showed the optimized result by using partially purified $50{\mu}g/ml$ of rabbit anti-E. tarda Edk-2 antibody in sodium bicarbonate buffer for overnight incubation to cover the surface of polystyrene beads. Optimized immunoreaction was observed in the treatment of $50{\mu}g/ml$ of biotin conjugated antibody followed extravidin-peroxidase diluted 1 : 2,000 in PBS. The detectable concentrations of the this method were $1{\times}10^5$ cells/ml and $1{\times}10^5$ cells/ml expressed as the source of antigen amount for EDTA extraction and heat extraction, respectively. High cross-reaction of solid phase ELISA with the prepared rabbit and-E. tarda Edk-2 was observed against E. tarda strains isolated from flounder suffering from edwardsiellosis in aquatic farms of Korea. It suggested that the potential of this solid phase of ELISA technique is very powerful for the application to different strains of E. tarda isolated in farms of many different areas.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.11 no.4
• /
• pp.315-319
• /
• 2001

A diagnosis system that provides early warnings regarding machine malfunction is very important for rolling mill so as to avoid great losses resulting from unexpected shutdown of the production line. But it is very difficult to provide e8rly w, ul1ings in rolling mill. Because dynamics of rolling mill is non-linear. This paper shows a chaotic behaviour of vibration signal in rolling mill using embedding method. Phase plane and Poincare map, FFT and histogram of vibration signal in rolling mill are implemented by qualitative analysis and Fractal dimension, Lyapunov exponent are presented by quantitative analysis.

• Proceedings of the KIEE Conference
• /
• 2007.07a
• /
• pp.1449-1452
• /
• 2007

배전 케이블 부분방전 측정에서는 외부노이즈, 코로나가 동반되어 검출되고 있다. 특히, 단말부의 부분방전측정에서는 부분방전 현상이 크게 발생하여 측정될 경우 다른 상에서도 유입되어 검출되는데 코로나나 외부의 노이즈가 크게 유입될 경우 진단의 어려움이 있다. 더불어 각 상의 위상을 직접검출이 어려운 송배전 케이블의 단말에서는 유기된 신호의 상을 찾는데도 어려움을 주고 있다. 이러한 문제를 반영하여 현장 측정이 용의하도록 이동형 포터블 진단장치를 개발하였다. 3개의 HFCT 센서를 사용하여 3상을 동시 측정할 수 있도록 하였다. 전원 분압 트리거 회로와 전류 변류 트리거 회로를 사용하여 위상 분석을 병행하였다. 실선로의 배전 케이블 부분방전 진단의 효율적 수행을 위해 개발된 본 장비를 현장 적용하였으며 내장된 PRPD 분석법이 가능하였으며 S/W 노이즈 게이팅을 적용하여 다른상에서 유기되는 신호를 제거하여 진단결과의 신뢰성을 높일 수 있었다.

• Applied Chemistry for Engineering
• /
• v.28 no.4
• /
• pp.397-403
• /
• 2017

The number of patients suffering from Alzheimer's disease is increasing year after year and almost approaching 15% of the total elderly population. Although it is critical to detect the early stage of Alzheimer's disease, which is a serious illness causing cognitive deficits, various existing diagnosis methods such as MRI, PET and CSF analysis could be the burdens for patients due to their high costs and long time to diagnosis. In order to tackle some of challenging issues for such existing diagnosis methods, extensive efforts have been made on developing fast and convenient biochip sensing methodologies for the diagnosis of Alzheimer's disease with a droplet of patient biofluids (e.g., blood). In this mini-review, we highlight some of the latest biochip sensing technologies that could qualitatively and quantitatively analyze blood biomarkers used for Alzheimer's disease diagnostics and discuss briefly related research trends and future aspects.