• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.13 no.9
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• pp.703-712
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• 2003

This paper suggests a fuzzy expert system for fault diagnosis of rotating machinery, based on modulated databases. In the proposed system, alarm and trip levels are set based on ISO, considering operating condition, machinery type and maintenance history. Input signals for diagnosis, such as sub-and super-harmonic components of vibration and mean value, are normalized from 0 to 1 under the threshold level and otherwise equal to one so that chronic faults slightly below the threshold level can be monitored. The database for diagnosis consists of two modules: the well-known Sohre's chart module and if-then type rules. The Sohre's chart is utilized for the most common problems of high-speed turbomachinery, while the rule-based module, which was collected from many papers and reports, is for diagnosing peculiar faults according to the type of machinery. To infer the results from two modules, a fuzzy operation of Yager sum was adopted. Using a simulator constructed in laboratory, experimental verification was performed for the cases of unbalance and resonance which were intended. The experimental results show that the proposed fuzzy expert system has feasibility in practical diagnosis of rotating machinery.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.303-312
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• 2003

This paper suggests a fuzzy expert system for fault diagnosis of rotating machinery, based on modulated databases. In the proposed system, alarm and trip levels are set based on ISO, considering operating condition, machinery type and maintenance history. Input signals for diagnosis, such as sub- and super-harmonic components of vibration and mean value, are normalized from 0 to 1 under the threshold level and otherwise equal to one so that chronic faults slightly below the threshold level can be monitored. The database for diagnosis consists of two modules: the well-known Sohre's chart module and if-then type rules. The Sohre's chart is utilized for the most common problems of high-speed turbomachinery, while the rule-based module, which was collected from many papers and reports, is for diagnosing peculiar faults according to the type of machinery. To infer the results from two modules, a fuzzy operation of Yager sum was adopted. Using a simulator constructed in laboratory, experimental verification was performed for the cases of resonance and housing looseness which were intended. The experimental results show that the proposed fuzzy expert system has feasibility in practical diagnosis of rotating machinery.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.05a
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• pp.547-549
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• 2012

In this paper, we propose the verification platform for traffic information of TPEG. Verification platform contains the parsing module of TPEG data and the processing module of GPS data. We compared the traffic information of GPS devices with traffic information of TPEG data. As a result, traffic information from TPEG data is distinguished from actual road traffic information.

• The Journal of the Korean life insurance medical association
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• v.26
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• pp.41-53
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• 2007

In the course of insurance claim administration, medical experts' opinions are called medical claim reviews. They are classified into two main categories: medical verification and counsel for claim staff. Medical verification compare between product coverage and the insured's physical condition. Medical counsel for claim staff is advice for claim staff when they have a question about medical knowledge to make a claim decision. A common example of medical verification is insurance coding of pituitary apoplexy. Some clinicians have insisted that the ICD coding of pituitary apoplexy is l63 of cerebral infarction, but the exclusion criteria of I code show that neoplasm is coded as C00 to D48. Thus, pituitary apoplexy must be coded as D33. An example of medical counsel for claim staff is interpretation of some medical conditions. It is divided into UCR(usual, customary, and reasonable) assessment, assessment of causality, and so on. Disability evaluation is another subject of medical counsel for claim staff. The final claim decision must be made by claim staff because only the claim staff have the authority of claim decision. Medical claims review is only an expert's opinion.

• The Journal of Korea Assosiation for Disability and Oral Health
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• v.14 no.2
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• pp.111-120
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• 2018

The need for oral health rights for people with disabilities is very high, and current oral health care system does not fully reflect these demands. Efforts to promote oral health of people with disabilities are urgently needed. In order for the disabled to have oral health rights, access to oral health services for people with disabilities should be improved and barriers to access should be resolved. In this study, we propose oral health service delivery system to guarantee oral health rights for the disabled. In addition, before applying the proposed oral medical delivery system, the external effects of the system application were predicted and the expert verification was conducted to find out the solution. There are some controversies about the development of the service delivery system proposed in this study. As a result of the expert verification, there were disagreements about the suitability of the service provider, the suitability of the service recipient, the appropriateness of the service content and scope, and the appropriateness of the cost and the revenue source. Subsequent Delphi surveys require the development of structured questionnaires for discussions that require consensus. It is expected that a reasonable consensus of expert opinions will be derived.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.75-80
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• 2005

A design for the front section of an excavator requires kinematic and kinetic mechanism consideration for several configurations. Key parameters for an appropriate configuration can be obtained through a mechanical verification and numerical formulation with a design expert's know-how. In this paper, we propose a knowledge-based system with an expert-shell(CATIA) and Visual Basic to assist for the design of the front section of an excavator. The designers can achieve more efficient design through a CAD model, implemented design knowledge, and a user friendly interface. The implemented design knowledge is retrieved through the whole design process from an early design stage to a detailed design stage based on the multiple levels of abstraction scheme.

• Proceedings of the KIEE Conference
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• 1999.07c
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• pp.1394-1396
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• 1999

It is important the protective relay should have high selectivity and sensitivity performance and it is achieved by correct setting of the relay parametes. The verification of accurate setting for the protective relay is very difficult before a actual fault occurs. This paper reports a diagnosis expert system to verify the correctness of the relay setting by using the operation results in the power system fault simulation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1995.10a
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• pp.30-36
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• 1995

Conventionally design for multi-stage cold forging depends on the designer's experience and decision-making. Due to such non-deterministic nature of the process sequence design, a flexible inference engine is needed for process design expert system. In this study, A* searching algorithm was introduced to arrive at the vetter process sequence design considering the number of forming stages and levels of effective strain, effective stress, and forming load during the porcess. In order to optimize the process sequence in producing the final part, cost function was defined and minimized using the proposed A* searching algorithm. For verification of the designed forming sequences, forming experiments and finite element analyses were carried out in the present investigation. The developed expert system using A* searching algorithm can produce a flexible design system based on changes in the number of forming stages and weights.

• The Transactions of the Korea Information Processing Society
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• v.4 no.2
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• pp.430-440
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• 1997

The knowledge repressenatation technique by production rule has been popular method to represent to represent the experts'dxpertise in expert systems.In this paper,we propose a method to verify the integrity of rule base.Proposcd method models rule base as a Petri net and utilizes the systematic strucutural properties of the petri net for berifi-cation.We describe the pricesure to check rule base at both local and global level intermal verification.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.171-174
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• 1997

In this study, a computer program was developed which generates automatically a drawing of the forging design in axisymmetric hot-forging of steel. The program designs a forging envelope from a machined part geometry according to forging design rules: parting line, draft angles, fillet and corner radii, minimum web and rib thicknesses. For the purpose of verification, the program was applied to a machined part from a factory. It was found that the generate forging design agreed well with the actual one used in the factory.