• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.395-400
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• 2004

For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established. Bearing diagnosis system is composed of four parts as follows : sensing part for ultrasonic sensor and preamplifier, signal processing part for measuring frequency spectrum, energy and amplitude, interface part for connecting ultrasonic signal to PC using A/D converter, graphic display and software part for display of bearing condition and for managing of diagnosis program.

• 대한기계학회논문집A
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• 제32권7호
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• pp.583-589
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• 2008

For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established. Bearing diagnosis system is composed of four parts as follows : sensing part for ultrasonic sensor and preamplifier, signal processing part for measuring frequency spectrum, energy and amplitude, interface part for connecting ultrasonic signal to PC using A/D converter, graphic display and software part for display of bearing condition and for managing of diagnosis program.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1727-1732
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• 2004

For the purpose of monitoring by ultrasonic test of the ball bearing conditions in rotating machinery, a system for their diagnosis was developed. ultrasonic technique is used to detect abnormal conditions in the bearing system. And various data such as frequency spectrum, energy and amplitude of ultrasonic signals, and ultrasonic parameters were acquired during experiments with the simulated ball bearing system. Based on the above results and practical application for power plant, algorithms and judgement criteria for diagnosis system was established.

• 보험의학회지
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• 제2권1호
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• pp.245-252
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• 1985

Ultrasonographic examination in the obstetrics not only makes easy of the diagnosis of Hydrocephalus, placenta previa, anencephalus and ectopic pregnancy, etc, but also guaranteed its excellence in the diagnosis of women gynecology disease. Especially in case that it doesn't affect radiation hazard on the embryo, its efficiency keeps increasing and it is spotlighted to many clinic doctors. Even though in general hospital we often observe congenital hydrocephalus in Med. Dept. which entirly undergoes the medical examination to the insured, we don't observe even the women delivered with child and it is very difficult to find a rare congenital hydrocephlus throughout other present insurance companies. We inspected a congenital hydrocephalus, which other medical equipments of present insurance companies have many difficulties in the medical examination, accompanied by meningoencephalocele by ultrasonic diagnosis. We analyzed and compared the data by ultrasonic diagnosis with that of surgical diagnosis and the results are follows; 1) We could correctly describe meningoencephalocele by ultrasonic diagnosis. 2) It was able to be diagnosed in LMP 22 weeks. 3) BPD has about 10 mm higher than normal value in LMP 22 weeks. 4) Dilatation of lateral ventricle was observed in LMP 22 weeks. 5) As paralled with ultrasonic diagnosis in pregnancy medical examination, accepting declines including the risk rate can be restrained.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.29-34
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• 2006

In this paper, the mechanical characteristics of ultrasonic cold forged technology (UCFT) used for the trimming knife and the effects of ultrasonic vibration energy (UVE) into the trimming process on the state of the strip cutting face were studied. And a diagnosis system to quality control for trimming knife and strip cutting face was developed and installed in plant. By the plant application of UCFT, service life of knife was more increased over 100% than that of conventional knife. And using the developed diagnosis system, the knife breakage and saw ear have been perfectly detected and quality control of trimming face is obtained effectively.

• 한국생산제조학회지
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• 제18권6호
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• pp.604-613
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• 2009

Recently, researches to develop phased array ultrasonic examination techniques are proceeded to diagnose dental caries and the status of surgical operation of dental implant. Sound field analysis of phased array ultrasonic transducers were carried out in order to characterizing the ultrasonic phased array beams. The sound field of ultrasonic radiation was calculated for the sample called "gypsum-improved stone" with the similar characteristics of dental materials. Industrial phased array ultrasonic devices were utilized for the insptriion of the artificial flaws machined in the gypsum-improved stone. Dental implants were made at the pig jaw bone and defect images were confirmed for the dental implants.

• 동력기계공학회지
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• 제17권4호
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• pp.31-35
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• 2013

The emergency AC power supply system of the nuclear power plant is designed to supply the power to the nuclear power plant at the emergency operating condition. The safety function of the diesel generator at the nuclear power plant is to supply AC electric power to the safety system whenever the preferred AC power supply is unavailable. The reliable operation of onsite standby diesel generator should be ensured by a condition monitoring system designed to maintain, monitor and forecast the reliability level of diesel generator. The purpose of this paper is to improve the existing ultrasonic sensor used for condition diagnosis of engine fuel pump and cylinder head for the accurate diagnosis in actual engine condition of emergency diesel generator(EDG). As a result of this study, we could design and develop much more reliable ultrasonic sensor than existing ones.

• 대한치과의사협회지
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• 제55권11호
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• pp.800-807
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• 2017

Ultrasonography is one of the most common diagnostic tools in medical imaging with non-invasive and non-radiation loaded characteristics. In the field of dentistry, especially for periodontology, high frequency ultrasonic device can be used for several purposes such as evaluating gingival thickness, identifying the level of alveolar bone, measuring the volume of mucosa of donor site for soft tissue graft and so on. According to recent studies, it was demonstrated that ultrasonic diagnosis had both accuracy and repeatability comparable to conventional diagnostic tools. However, improvement and development of intra-oral probe suitable for adpatation to gingiva and palatal mucosa, are considered as prerequisites for diffusion of ultrasonic diagnosis in periodontology.

• 대한전기학회논문지:전기물성ㆍ응용부문C
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• 제54권12호
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• pp.553-557
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• 2005

This paper describes the application results of an ultrasonic detection system for the power transformer. The ultrasonic detection system with 6 sensors was applied to detect partial discharge in a 154kV transformer with a dangerous levels of $C_{2}H_{2},\;C_{2}H_4$ and $CH_{4}$ gases. The ultrasonic detection tests were carried out 2 times, respectively, to confirm the existence and location of the partial discharge in the transformer. As a result of internal inspection, the arc trace between the pressure ring and core due to the partial discharge was found at the estimated position based on the amplitude and arriving time of the ultrasonic signals. Therefore, it was verified that the ultrasonic detection system is effective as a preventive diagnosis method for the power transformer. Also, the reliability of the ultrasonic detection system in detecting partial discharges in the transformer was also confirmed. It is expected, therefore, that the ultrasonic detection system will have beneficial effects on applications and verifications in detecting partial discharges for the power transformer.

• 비파괴검사학회지
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• 제22권4호
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• pp.377-385
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• 2002

비전리 방사선을 이용하는 초음파 탐상법은 안전하며 사용이 간편하기 때문에 비파괴검사에서 매우 선호되고 있는 방법이다. 의학적으로 초음파 탐상법은 동일한 원리를 이용하여 인체의 결함 즉 질병의 진단을 위해 유용한 수단 요로 활용되고 있다. 본 논문에서는 초음파 탐상법에 기반한 의료용 초음파 진단의 원리에 대해 개관하고, 그동안 임상적으로 별로 주목받지 못한 초음파 C스캔 영상을 이용한 치밀골의 미세 골절 진단 가능성을 실험적으로 평가하였다. 실험에서는 돼지 대퇴골에 3점 굽힘 힘 (2-4 kN)을 1 mm/min 속도로 가해 미세 골절을 유발하였다. 골절의 정도를 변화하면서 골절에 대한 엑스선 영상과 25 MHz 접속형 초음파 변환기롤 이용하여 C스캔 영상을 취득하였다. 실험 결과 초음파 C 스캔 영상은 기존의 골절 진단법인 엑스선 영상에서는 진단이 어려운 미세한 골절까지 감지할 수 있음을 확인하였다.