• Journal of Periodontal and Implant Science
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• v.31 no.1
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• pp.257-269
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• 2001

Removal of subgingival calculus is essential for the success in periodontal treatment. Subgingival instrumentation is used for the removal of all bacterial plaque and calculus. In this study, Gracey curet and Ultrasonic curet were used on single rooted teeth to conduct subgingval scaling and root planning. The remaining amount of calculus was evaluated according to type of instrument, depth of pocket, and tooth surface. 24 teeth were extracted from 14 patients being treated at department Periodontology Seoul Advantist dental hospital were used. Total 96 area(4 surface per teeth) were evaluated. 12 teeth treated with Gracey curet were used as the control group and the other 12 teeth treated with Ultrasonic curet were examined for experimental group. The 4 surface of the teeth(buccal, mesial, lingual or palatal, distal) were observed through the stereomicroscope and the images of the surface were captured and saved in CCD. The images were displayed on the monitor and the amount of calculus remained was evaluated by overlapping $10{\times}10$ grid pixel screen produced by Microsoft power point. The results evaluated were as follows 1. There was no statistically significant difference in residual calculus and tooth position following scaling and root planning of all group, but statistically significant correlation with residual calculus, probing depth, instruments and tooth surface. 2. There was statistically significant correlation between residual calculus and probing depth, but no statistically significant difference in residual calculus, tooth surface and tooth position on experimental(Ultrasonic curet) group. 3. There was no statistically significant difference in residual calculus according to the pre-treatment pocket depth and tooth position, but statistically significant correlation with tooth surface. The amount of residual calculus increase with mesial, distal, buccal and lingual(or palatal) surface on control(Gracey curet) group. 4. The Gracey showed better results than ultrasonic curet in mesial and distal surface, and there is significant difference. The results demonstrate that ultrasonic curet alone is inadequate for thorough subgingival debridement and suggest that Ultrasonic curet with Gracey curet should be more effective.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.3
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• pp.275-281
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• 2004

Socket weldment used to change the flow direction of fluid nay have flaws such as lack of fusion and cracks. Liquid penetrant testing or Radiography testing have been applied as NDT methods for flaw detection of the socket weldment. But it is difficult to detect the flaw inside of the socket weldment with these methods. In order to inspect the flaws inside the socket weldment, a ultrasonic testing method is established and a ultrasonic transducer and automated ultrasonic testing system are developed for the inspection. The automated ultrasonic testing system is based on the portable personal computer and operated by the program based Windows 98 or 2000. The system has a pulser/receiver, 100MHz high speed A/D board, and basic functions of ultrasonic flaw detector using the program. For the automated testing, motion controller board of ISA interface type is developed to control the 4-axis scanner and a real time iC-scan image of the automated testing is displayed on the monitor. A flaws with the size of less than 1mm in depth are evaluated smaller than its actual site in the testing, but the flaws larger than 1mm appear larger than its actual size on the contrary. This tendency is shown to be increasing as the flaw size increases. h reliable and objective testing results are obtained with the developed system, so that it is expected that it can contribute to safety management and detection of repair position of pipe lines of nuclear power plants and chemical plants.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.943-944
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• 2013

• Proceedings of the KSR Conference
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• 1998.11a
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• pp.296-301
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• 1998

Pentagraphs are used to supply electric power to train via trolley lines. The higher train speed is, the higher voltage and current levels 8u. Since electric power is supplied with slinding contact, localized abrasion is inevitable. It is difficult and dangerous to measure their shape manually. Measurement system of pentagraph slider with ultrasonic processing has been reported. In this paper, measurement system with image processing is proposed. The system consists of CCD cameras, image grabber board, and PC operated on Windows'95. Image processing algorithms are presented and some results are illustrated.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.45 no.3
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• pp.319-331
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• 2019

This study was conducted to find a solvent, a extraction method and optimized conditions for Artemisia iwayomogi extract. which is effective to anti-inflammatory and antioxidant activity. A. iwayomogi extract by distilled water, ethanol, methanol, hexane and ethyl acetate using ultrasonic, high-pressure and supercritical extraction was investigated for NO inhibitory and DPPH radical scavenging activity. Extract obtained by ethanol and ultrasonic extraction method showed high NO production inhibitory activity, DPPH free radical scavenging activity and yield. Response surface methodology (RSM) was applied to find a optimized ultrasonic extraction conditions. Results showed that the optimum conditions for the higher yield were ethanol solvent of 45.71% concentration with extraction time and ultrasonic power of 63.33min and 308.84 W, respectively. This condition predicted 15.85% yield, but real yield was $16.40{\pm}0.28%$. The optimum conditions for simultaneous anti-inflammatory and antioxidant activity were established as ethanol concentration (80.81%), extraction time (90.00 min) and ultrasonic power (400.00 W). NO production inhibitory and antioxidant activity were $89.77{\pm}1.37%$ and $60.12{\pm}0.39%$, respectively. These results showed similar to the predicted values of 94.54%, 58.03% respectively.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2010.10a
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• pp.515-516
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• 2010

• Journal of the Korean Society for Nondestructive Testing
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• v.6 no.2
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• pp.57-70
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• 1987

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.445-448
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• 1997

• Environmental Engineering Research
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• v.8 no.2
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• pp.59-71
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• 2003

• Proceedings of the Korean Nuclear Society Conference
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• 2005.05a
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• pp.823-824
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• 2005