• Journal of the Institute of Convergence Signal Processing
• /
• v.5 no.4
• /
• pp.281-286
• /
• 2004

The wear process of end mill is a so complicated process that a more reliable technique is required for the monitoring and controling the tool life and its performance. This research presents a new tool wear monitoring method based on the sound signal generated on the machining. The experiment carried out continuous-side-milling for using the high-speed steel end mill under wet condition. The sound pressure was measured at 0.5m from the cutting zone by a dynamic microphone, and was analyzed at frequency domain. The tooth passing frequency appears as a harmonics form, and end mill wear is related with the first harmonic. It can be concluded from the result that the tool wear is correlate with the intensity of the measured sound at tooth passing frequency estimation of end mill wear using sound is possible through frequency analysis at tooth passing frequency under the given circumstances.

• 대한공업교육학회지
• /
• v.31 no.1
• /
• pp.185-199
• /
• 2006

In this paper, to detect lateral direction sound pressure fiber optic sensor using Fabry-Perot interferometeric sensor array was fabricated and experimented. This parallel sensor array composed of one light source and the light split into each sensor using directional coupler and to see the output signal the array system do not need any digital signal processor. As a lateral direction sound source arbitrary sound frequency of 100Hz, 200Hz, and 655Hz using by nondirectional speaker were applied to the array sensor which installed on $60cm{\times}60cm{\times}60cm$ latticed structure. The detected signals from the two sensors were analyzed in the time and frequency domains. It was confirmed that the suggested sensor array detected applied sound source well but there were a little amplitude differences in between the sensors. Because the sensor supported simply at both ends theoretical analysis was performed and its solution was suggested. To compare the theoretical and experimental results arbitrary sound frequency of 2kHz was applied to the sensor array. It shows that experimental results was good agreement with theoretical results.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.11a
• /
• pp.330-332
• /
• 2003

In this paper, It is introduced new sound quality method, FI(Fluctuation Index) and the example applied Outdoors side Air-conditioner noise evaluation. Because FI is applied with very simple algebraic calculation algorithm, it can be applied some other application without spending high time and cost.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.363-364
• /
• 2006

The direction of arrival of the sound signal can be derived from the time differences at the microphone array and the motor controls the camera to point at the direction of the sound signal. You can get through to the homepage and confirm the camera image on a client computer which connects to the server computer through Internet.

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.341-342
• /
• 2006

The direction of arrival of the sound signal can be derived from the time differences at the microphone array and the motor controls the camera to point at the direction of the sound signal. You can get through to the homepage and confirm the camera image on a client computer which connects to the server computer through Internet.

• Proceedings of the IEEK Conference
• /
• 1998.10a
• /
• pp.1243-1246
• /
• 1998

Three-dimensional(3-D) sound is a technique for generating or recreating sounds so they are perceived as emanating from locations in a three-dimensional space. Three dimensional sound has the potential of increasing the feeling of realism in music or movie soundtracks. Three-dimensional sound effects depend on psychoacoustic spectral and phase cues being presented in a reproduced signal. In this paper we propose an effective algorithm for the sound image expansion in television system using stereo image enhancement techniques. Compared to the other techniques of three-dimensional sound, the proposed algorithm use only two speakers to enhance the sound image expansion, while maintaining the original sound characteristics.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.11a
• /
• pp.682-685
• /
• 2005

In this research, how the evaluation of the spacial image influenced by the environmental friendly elements included in the visual information, and how the selection of the sound changed depending on the characteristics of spatial image by the 40 subjects were carried out. Vast tracts of green land and the waterfront were highly preferred and impressive than the other spaces. The green music, signal with water sound and bird chirping sound were highly scored. In the frequency characteristics of the factors, the first factor was artificial sound(high at the low frequency band), the second was natural sound(uniform at all frequency band) and the third was water sound(high at the middle and high frequency band over 500Hz). This shows that the proposal of the sound which has the frequency characteristics fit to the spacial image should be selected for the soundscape of the target space.

• 제어로봇시스템학회:학술대회논문집
• /
• 2005.06a
• /
• pp.872-876
• /
• 2005

We propose a real-time post processing of nonlinear amplified signal to improve voice recognition in remote talk. In the previous research, we have found the nonlinear amplification has unique advantage for both the voice activity detection and the sound localization in remote talk. However, the original signal becomes distorted due to its nonlinear amplification and, as a result, the rest of sequence such as speech recognition show less satisfactorily results. To remedy this problem, we implement a linearization algorithm to recover the voice signal's linear characteristics after the localization has been done.

• Proceedings of the KIEE Conference
• /
• 1997.11a
• /
• pp.597-599
• /
• 1997

Cochannel speaker separation is employed when speech from two talkers has been summed into one signal and it is desirable to recover one or both of the speech signals from the composite signal. Cochannel speech occurs in many common situations such as when two AM signals containing speech are transmitted on the same frequency or when two people are speaking simultaneously (e. g., when talking on the telephone). In this paper, the method that separated the speech in such a situation is proposed. Especially, only the voiced sound of few sound states is separated. And the similarity of the signals by the cross correlation between the signals for exactness of original signal and separated signal is proved.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.05a
• /
• pp.635-639
• /
• 2003

When we carry out acoustic holography, step-by-step measurement provides us larger aperture size with same number of microphones. But when we carry out step-by-step measurement, it is blown that sound signal must be stationary. However, when transfer function between input and output signal is time-invariant, we can apply step-by-step measurement to acoustic holography even if sound signal is transient We have to do only some Processing on signals from step-by-step measurements to make the signal data of each step compatiable with other steps. This paper accounts for that processing method.