• Textile Coloration and Finishing
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• 제8권4호
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• pp.59-68
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• 1996

섬유산업에 초음파의 이용은 극히 새로운 것이 아니며, 초음파를 이용하여 시간단축과 공정개선 등에 관한 많은 문헌들도 있다. 게다가 세정과 기계분야, 안정된 분산용액의 제조에 두드러지게 활용되고 있는 기술이며, 다른 새로운 분야로도 연구확대되고 있다. 주로 세정조에 구성되어 있는 초음파발생자치는 세정효율을 높이기 때문에 응용확대가 기대된다. 특별한 장치가 필요없기 때문에 음화학반응에서 관심이 모아지고 있다. 초음파는 이제 광범위한 습식공정에 영향을 미치는 기술로 이해되고 있다. 이 자료는 이미 연구된 결과를 재조명하고 초음파를 이용하므로서 얻을 수 있는 이점에 대해서 어떤 것이 있는지에 대해 살펴보고자 한다.

• Journal of Biomedical Engineering Research
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• 제7권2호
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• pp.139-146
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• 1986

Pulsed ultrasonic Doppler system is a useful diagnostic instrument to measure blood-flow-velocity, velocity profile, and volume-blood-flow. This system is more powerful compare with 2-dimensional B-scan tissue image. A system has been deve- loped and ii being evaluated using TMS 32010 DSP. We use this DSP for the purpose of real-time spectrum analyzer to obtain spectrogram in singlegate pulsed Doppler system and for the serial comb filter to cancel clutter and zero crossing counter to estimate Doppler mean frequency in multigate pulsed Doppler system. The Doppler shift of the backscattered signals is sensed in a phase detector. This Doppler signal corresponds to the mean velocity over a some region in space defined by the ultrasonic beam dimensions, transmitted pulse duration, and transducer ban(iwidth. Multi- gate pulsed Doppler system enable the transcutaneous and simultaneous assessment of the velocities in a number of adjacent sample volumes as a continuous function of time. A multigate pulsed Doppler system processing the information originating from presented.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.162-163
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• 2009

본 연구에서는 초음파 진동자를 적용한 초극세사 자동 절단 시스템을 개발 하였다. 초극세사 자동 절단 시스템은 공진 주파수 28kHz를 가지는 초음파 진동자, 구동회로부, 원단 이송장치, 초음파 진동자 이송장치, 초극세사 원단과 에어실린더 사이의 정전기 발생을 방지하기 위한 정전기 제거장치, 구동모터, 및 절단 크기와 절단 속도 등을 조절하기 위한 전기제어 판넬로 구성하여 제작하였다. 또한, 개발한 절단 시스템을 이용하여 초극세사 클리너 시제품을 제작하여 절단면을 전자현미경으로 관찰하였고, 절단 시스템의 소음진동 특성을 평가하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1241-1246
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• 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 Machine Tool Engineers Conference
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• 한국공작기계학회 2003년도 춘계학술대회 논문집
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• pp.371-375
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• 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.

• The Journal of the Acoustical Society of Korea
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• 제15권1호
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• pp.10-16
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• 1996

Ultrasonic motor is a motor driven by the stator via frictional contact forces generated from ultrasonic vibration of piezoelectric elements. In order to control the ultrasonic motor, it is essential to measure accurately the motor characteristics with respect to driving parameters such as frequency, voltage, phase difference and duty ratio of the driving signals. In this paper, a PC-interfaced evaluation device is developed, and the characteristic curves of the fabricated ultrasonic motor are measured with those parameters. All driving parameters are processed digitally. The developed evaluation device can facilitate charateristics measurements effectively, and provide a base for digital control of the ultrasonic motor.

• Proceedings of the KIPE Conference
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• 전력전자학회 2011년도 전력전자학술대회
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• pp.537-538
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• 2011

본 논문에서는 전동 휠체어를 이용하여 이동할 때 안전운전을 위한 반 자율 보조 장치를 제안한다. 제안된 전동 휠체어 보조 장치는 장애물 감지를 위한 초음파 센서와 현재 방향과 위치를 확인하기 위한 엔코더를 사용하여 이동시 발생할 수 있는 안전사고를 미연에 방지할 수 있도록 설계하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.327-328
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• 2006

Recently, as the infocomindustry is developed, the semiconductor industry as well as the optical industry such as the optical communication and the optical instrument is developed rapidly. The transmission, storage and processing of information has been reaching an limit because amounts of information increase rapidly. The more quickly the optical communication is developed, the more sharply the demand of optical elements increase. The transport and inspection process is time consuming and the error rate is high, because this process are not automated in case of an optical lens. In this paper, the pick-up system that can hold optical elements and be transferred by the ultrasonic transport system is developed. The inspection system that distinguishes between the existence and the nonexistence of a defect is connected easily to pick-up system. The pick-up system separates the optical glass lens by results of the inspection. The automation program is developed by visual c++ programming.

• Journal of the Korea Institute of Building Construction
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• 제24권1호
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• pp.67-75
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• 2024

In the context of Korean residential heating systems, Ondol pipelines are a prevalent choice. However, the maintenance of these pipelines becomes a complex task once they are embedded within concrete structures. As time progresses, the accumulation of sludge, corrosive oxides, and microorganisms on the inner surfaces of these pipelines diminishes their heating efficiency. In extreme scenarios, this accumulation can induce corrosion and scale formation, compromising the system's integrity. Consequently, this research introduces an ultrasonic generation system tailored for the upkeep of Ondol pipelines, with the objective of empirically assessing its practicality. This investigation delineates three variants of ultrasonic generating apparatuses: those employing surface vibration, external generation, and internal generation techniques. To emulate the presence of contaminants within the pipelines, substances in powder, slurry, and liquid forms were employed. The efficacy of the cleaning process post-ultrasonic wave application was scrutinized over time, with image analysis methodologies being utilized to evaluate the outcomes. The findings indicate that ultrasonic waves, whether generated externally or internally, exert a beneficial effect on the cleanliness of the pipelines. Given the inherent characteristics of Ondol pipelines, external generation proves impractical, thereby rendering internal generation a more viable solution for pipeline maintenance. It is anticipated that future endeavors will pave the way for innovative maintenance strategies for Ondol pipelines, particularly through the advancement of internal generation technologies for pipeline applications.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 한국정밀공학회 1993년도 춘계학술대회 논문집
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• pp.151-154
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• 1993

지동 및 음향분야의 발달과 더불어 가청주파수 이상의 초음파에대한 연구가 여러분야에 걸쳐 다양하게 많은 학 자들에 의해진전되어 왔다. 이중에서 실용적인 초음파 장치가 처음으로 등장한 것은 1921년경 프랑스의 랑지방 (P. Langevin)에 의해 만들어진 초음파측심기라고 전해지고 있다. 당시 사용된 진동자는 두 장의 금속원판 사이에 수정을 샌드위치 형태로 만든것으로써 랑지방형 진동자라고 한다. 최근 각종기계의 경량화, 고도화, 고성능화가 요구 되면서 고인성, 고내열성, 고경도 등의 특성을 갖는 재료를 가공함에 있어서 저동력 및 고정밀도가 요구되고 있다. 본 연구에서는 선삭가공에서 초음파발생기에서 보낸 초음파신호를 초음파 진동혼의 설계에 의한 진폭을 증가시켜 사각형 단면을 갖는 양단자유지지 굽힘진동 공구홀더의 공진조건을 초음파 진동절삭 가공시스템에 적용시키는데 목표를 두며 또한 초음파 진동절삭을 적용시켰을 때의 절삭 특성을 규명하기 위하여 선정된 절삭조건으로 선삭할 때 발생하는 절삭분 력 및 표면거칠기를 측정하고 분석하여 그 결과로부터 절삭특성을 해석코자 본 연구를 수행하였다.