• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2005.05a
• /
• pp.264-268
• /
• 2005

In the semiconductor and optical industry the non-contact transportation is required for reducing the damages. The ultrasonic levitation is the solution of the problem. In this paper, the ultrasonic levitation system and 3 disk-type stator for levitating various object are proposed. The vibration modes of disks are analyzed with FEM and designed with the analysis results. The 3D vibration profiles of the disks are measured by Laser scanning vibrometer for verifying the vibration characteristics of the system and the amplitudes of the disks and the levitation heights of object are measured for evaluating the performance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2007.11a
• /
• pp.1241-1246
• /
• 2007

In recent years, the semiconductor industry and the optical industry are developed rapidly. The recent demands have expanded for optical components such as the optical lens, the optical semiconductor and the measuring instrument. Object transport systems are driven typically by the magnetic field and the conveyer belt. Recent industry requires more faster and efficient transport system. However, conventional transport systems are not adequate for transportation of optical elements and semiconductors. The conveyor belts can damage precision optical elements by the contact force and magnetic systems can destroy the inner structure of semiconductor by the magnetic field. In this paper, the levitation transport system using ultrasonic wave is developed for transporting precision elements without damages. The steady state flexural vibration of the beam is expressed using Euler-Bernoulli beam theory. The transport direction of an object is examined according to phase difference and frequency. The theoretical results are verified by experiments.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2005.06a
• /
• pp.1527-1530
• /
• 2005

In the semiconductor and optical industry the non-contact transportation is required for reducing the damages. The ultrasonic levitation is the solution of the problem. In this paper, the ultrasonic levitation system and 3 disk-type stator for levitation various object are proposed. The vibration modes of disks are analyzed with FEM and designed with the analysis results. The 3D vibration profiles of the disks are measured by Laser scanning vibrometer for verifying the vibration characteristics of the system. The amplitudes of the disks and the levitation heights of object are measured for evaluating the performance.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1170-1173
• /
• 2003

In the semiconductor and the optical industry a new transport system which can replace the common system is required. The common systems are driven by magnetic field and conveyer belt. The magnetic field damages semiconductor and contact force scratches, the optical lens. The ultrasonic wave driven system solve these problem. In this paper the object transport system using the excitation of ultrasonic wave is proposed. the experiments for finding the optimal excitation frequency, finding phase-difference between two ultrasonic wave generators are performed. The effect of transporting speed according to the change of amplification voltage is verified. In addition, the system performance for actual use is evaluated

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2003.04a
• /
• pp.371-375
• /
• 2003

In recent years, as the semiconductor and the optical industry grows, the necessity of the transporting system for semiconductor and precision optical lens without damage increases. The transport system using ultrasonic wave is very suitable for this area. In this paper the object transport system using the excitation of ultrasonic wave is proposed. The experiments for finding the optimal excitation frequency, finding phase-difference between two ultrasonic wave generators are performed. The effect of transporting speed according to the change of weight and amplification voltage are verified. In addition, the system performance for actual use is evaluated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.11a
• /
• pp.696-699
• /
• 2003

In the semiconductor and the optical industry a new transport system which can replace the conventional sliding system is required. There systems are driven by magnetic field and conveyer belt. The magnetic field damages semiconductor and contact force scratches the optical lens. The ultrasonic wave driven system can solve these problem. In this paper, the object transport system using the excitation of ultrasonic wave is proposed. The experiments for finding the optimal excitation frequency, finding phase-difference between two ultrasonic wave generators are performed. The relationship of transporting speed according to the change of flexural beam shape is verified and the system performance for practical use is evaluated.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.05a
• /
• pp.956-959
• /
• 2003

In the semiconductor and the optical industry a new transport system which can replace the common system is required. The common systems are driven by magnetic field and conveyer belt. The magnetic field damages semiconductor and contact force scratches the optical lens. The ultrasonic wave driven system solve these problem. In this paper the object transport system using the excitation of ultrasonic wave is proposed. The experiments for finding the optimal excitation frequency, finding phase-difference between two ultrasonic wave get orators are performed. The effect of transporting speed according to the change of weight and amplification voltage are verified. In addition, the system performance for actual use is evaluated.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
• /
• 1992.11a
• /
• pp.44-49
• /
• 1992

액체를 취급하는 기계.장치는 유속 및 회전속도 등이 빠르게 되면 유체충격과 정압의 저하에 따른 국부적 비등으로 인해 캐비테이션(cavitation) 현상이 발생한다. 이러한 캐비테이션현상에 따른 소음과 진동율 초래하고, 또한 기포의 붕괴에 따른 형격압으로 캐비테이션-침식(cavitation-erosion)이 발생하여 기계.장치의 구성재료에 손실이 일어남으로써 이들 기계의 효율을 저하시킴과 아울러 수명을 단종시킬 수 있다. 더욱이 부식성의 액체에 사용되는 기계.장치의 금속재료에는 캐비테이션(erosion-corrosion)이 중첩하여 발생하는 경우는 침식과 부식이 상호간에 가속하는 상승효과 때문에 기계.장치의 수명에 치명적인 영향을 미친다. 따라서 본 연구에서는 초음파 진동장치에 의한 각종 유중에서 베어링 합금 1종, 7종 및 켈-멧 4종에 대한 캐비테이션-침식실험을 실시하여, 침식손상거동및 특성등을 구명하고저 하였다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.12 no.1
• /
• pp.79-88
• /
• 2014

We have developed a smart decontamination device for small-size radioactive scrap metal (SSRSM) necessarily generated from nuclear facilities. This is a multi-modal device such as rotation of magnetic field focusing on the region containing the abrasion pins placed around target and ultrasonic cleaner. Additionally, in order to increase the decontamination efficiency we have modified some configuration of the device so that it could work on them evenly and totally. With the Optimal operating for operation of the new device, we tried to decontaminate some various metal selected as a sample during 15 minutes sequentially using each method, magnetic and ultrasonic device. As a result, the range of decontamination factor has been highly increased to 18~56. After decontamination, all samples were found its activity less than background level.

• The Journal of the Acoustical Society of Korea
• /
• v.22 no.2
• /
• pp.113-120
• /
• 2003

Rayleigh was an excellent experimenter as well as a theorist. Rayleigh improved Rijke's sounding device by heat and the singing flame into sources of pure tones. Above all, his making of the artificial bird whistle was a critical achievement in the improvement of experimental sound sources. This source made supersonic waves available in the laboratory and thus paved the way to confirmable observations of reflection, refraction, diffraction and interference of sound in the laboratory Furthermore, Rayleigh augmented the sensitivity of sensitive flames as detectors for sound wave. Besides, he devised a phonic wheel which could precisely control the angular velocity of some acoustical instruments and made the Rayleigh-disk that enabled experimenters to measure the absolute value of the sound intensity. These devices enhanced the exactness of acoustical experiments.