• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.382.1-382
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• 2002

This paper presents a new approach integrated Case-Based Reasoning with Self- Organization Map(SOM) in diagnosis systems. The causes of faults are obtained by case-base trained from SOM. When the vibration problem of rotating machinery occurs, this provides an exact diagnosis method that shows the fault cause of vibration problem. In order to verify the performance of algorithm, we applied it to diagnose the fault cause of the electric motor.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.144-145
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• 2010

3-D noise map of Mugue Dong of the Ulsan City has been constructed. Comparing with the measured noise level, the predicted noise level has been confirmed for its accuracy. Correction factors for better prediction result using the constructed noise map have been investigated proving that its method is useful. The procedure of noise map construction method has also been introduced using RLS-90, Cadna A.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.05a
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• pp.590-595
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• 2001

Vibration transient generated by developing localized fault in gear can be used as indicators of condition monitoring in a gear. In this paper, we propose the phase map for a fault signal using continuous wavelet transform to detect this vibration transient. Local fault induces the abrupt fluctuation of load exciting tooth and phase lag in the vibration signal measured on the gearbox. The relatively large fault like "tip breakage" easily can be detected by the clear fluctuation of exciting load. However, minor fault like "initial pitting" cannot be detected using the load fluctuation. To detect this kind of minor fault, the phase map for a fault signal is taken into account. The phase lag by minor fault is observed well in the phase map.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.142-143
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• 2010

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.193-194
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• 2011

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.208-211
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• 2005

This paper describes the development process of steering system for reduce idle vibration through the data level of frequency and sensitivity. High stiffness and light weight vehicle is a major target in the refinement of passenger cars to meet customers' contradictable requirements between NVH performance and fuel economy. The target frequency of the steering system is set by benchmarking of a competitive vehicle and the vibration mode map is used to separate steering column modes from resonance of body structure and engine idle rpm. This paper descirbes the analysis approach process for high stiffness of steering system and the design guideline is suggested about steering column and support system by using mother car at initial design stage. We used a patent map in order to analyze accurately a technical trend and suggested the design process using dynamic damper of steering system considering sensitivity. And we established techniques of analysis on steering system and evaluated the level of accuracy of analysis through correlating the test and analysis results. It makes possible to design the good NVH performance vehicle at initial design stage and save vehicles to be used in tests. These improvements can lead to shortening the time needed to develop better vehicles.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.11
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• pp.1759-1766
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• 2001

Vibration transient generated by developing localized fault in gear can be used as indicators in gear fault detection. In this paper, we propose the zoomed phase map for a fault signal using continuous wavelet transfers to detect this vibration transient. Local fault induces the abrupt fluctuation of load exciting tooth and phase lag in the vibration signal measured on the gearbox. The relatively large fault like "tip breakage" easily can be detected by the clear fluctuation of exciting load. However, minor fault like "initial pitting"cannot be detected using the load fluctuation. To defect this kind of minor fault, the phase map for a fault signal is taken into account. The phase lag by minor fault is observed well in the zoomed phase map.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.613-617
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• 2007

Noise maps of a city in Korea have been made using commercial noise map softwares by measuring the basic data in the city. The result in this study will be used to evaluate the environmental impact of noise from various noise sources and to implement the Korean noise map standard.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2003.05a
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• pp.1182-1186
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• 2003

Noise map is becoming an increasingly important tool supporting noise policy. In order to main am a quiet environment of urban areas, noise map was developed by using GIS technique which combines geographic and noise informations with a database management system. By evaluating various methods of the spatial anal: sis, it was concluded that the inverse distance weighted method gave the best results and was applied to develope the noise maps of road noise.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.11a
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• pp.778-781
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• 2004

Recently, one of the reason of noise problems is urban planning has little concern about noise. For solving noise problems, strategic action is needed during urban planning. The noise map is one of the solution for concerning about noise in urban planning and EC has been studied the noise map for the strategic purpose since 1970s. The noise map is powerful tool for predicting sound level, calculating exposure population and evaluating the efficiency of the noise reduction plan. In Korea, The noise map is a unfamiliar field. The experience is few for noise-mapping and the noise mapping procedure has not been standardization yet. For activation of noise map, the study about fundamental problems of collecting data md noise-mapping procedure must be need. This paper is for studying on the noise-mapping procedure in Korea and application of noise map.