• Journal of the Korean Society of Safety
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• v.13 no.3
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• pp.102-111
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• 1998

This study was concerned with the development of a heavy duty rust-converting agent, the function of which is to form metal complex coatings, containing vinyl halide-acrylic terpolymer emulsion, defoamer, emulsifying agent, glass flakes, chelating agent such as gallotannic acid, gallic acid, and pyrogallic acid, and other additives. The resulted emulsion products(Sample No.1~No.5) were characterized through test either in the forms of emulsions, which include Viscosity, Penetration rate, Acidity and Film drying rate test, or in the forms of coated layer on rusty steel substrates by FT-IR, which include hardness, gloss, salt spray, adhesion and flame retardant test. The test results are as follows ; Penetration rate(0.1~0.4 mm/min), Solid content(70%), Acidity (pH 1.8~2.0), Specific gravity(1.30~1.35), Film drying rate(108min, RH 40% ; 150min, RH 80%), Gloss(83~92, incident angle $60^{\circ}$; 88~97, incident angle $85^{\circ}$), Pencil hardness(4H~5H), Adhesion (100/100), Salt spray test(>720Hr), LOI(%) value(38%), Vertical burning test(UL 94-v-l). According to the various performance of specimens show above, the evaluation of the availability of this heavy duty rust-converting agent can be concluded that all the samples(No.1~No.5) are capable of being used in the field of chemical plant and in the hazard areas of fire and explosion potential. It was observed that the properties of sample No.2, especially gloss and hardness, were much better than that of the other samples.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.10
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• pp.41-46
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• 2003

This paper deals with the possibility of tap breakage detection by AE sensor. AE signals in the tapping were not seldom generated in low speed but reflected the tapping process exactly in high speed. Using AE raw signals sampled in 500kHz, AE RMS and AE count rate was computed in software. When the converting time of AE RMS is less than 10ms, we could distinguish between normal cutting and tap breakage. And AE count rate was more exact when the converting time is greater than 1ms. When two methods were compared to each other, AE count rate was more accurate.

• Korean Journal of Food Science and Technology
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• v.29 no.6
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• pp.1316-1318
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• 1997

The isolated ${\kappa}-Casein$ on gel permeation chromatography was hydrolyzed by chymosin, trypsin, and pepsin. The 3% TCA soluble portion of the hydrolysates were dialyzed on the angiotensin-I converting enzyme (ACE) inhibition rate (%,) and inhibitory activity $(IC_{50})$ were determined. The trypsin hydrolysate exhibited the highest ACE inhibition rate while the chymosin hydrolysation showed the lowest activity. The hydrolysate was dialyzed using dialysis membrane with various molecular cut-offs, and $IC_{50}$ was determined. As the pore size of the dialysis tubing increased, the ACE inhibitory activity decreased.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.4
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• pp.737-742
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• 2000

As functionality investigation of a soybean fermentation food, a angiotensin converting enzyme inhibitory peptide was separated during natto fermentation by Bacillus natto and inhibitory effect was investigated. After incubation at each 2$0^{\circ}C$, 3$0^{\circ}C$, 4$0^{\circ}C$, 5$0^{\circ}C$, 6$0^{\circ}C$ for the 0~72 hr, protein content, protease activity and angiotensin converting enzyme inhibition were determined. The protein content and protease activity were increased and reached maximum at 60 hr fermentation with 4$0^{\circ}C$ and decreased after the 60 hr fermentation during natto fermentation. The optimum condition for angiotensin converting enzyme inhibitors was appeared at fermentation for 60 hr at 4$0^{\circ}C$. Crude extract of natto was partially purified by Amicon membrane YM-3 and Sephadex G-10, G-25 gel filtration, stepwise. The inhibitory rate was increased in a concentration dependent manner, espcially the most potent activity about 74.74% at 1.0 mg peptide content. The most prominent amino acid of the peptide from natto was alanine, followed by phenylalnine, histidine.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.114-124
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• 2006

The objective of this research was to evaluate the ability of water and 80% ethanol extracts from one hundred eight mulberry leaves (Morus alba L.) to influence the inhibitory activity of angiotensin converting enzyme (ACE) and xanthine oxidase (XOase). The total phenol contents were that water extracts of ten species (Kakjayongsan (Morus alba L.), Daejungsun (Morus alba L.) etc.) and 80% ethanol extracts of twenty three species (Waryoung (Morus alba L.), Hasusang (Morus alba L.) etc.) showed more than 15 mg/g. The inhibitory activity on angiotensin converting enzyme (ACE) were that ten species (YamanakkadakKaskke (Morus alba L.), Mijiro (Morus alba L.) etc.) showed 100% inhibition rate both of water extracts and 80% ethanol extracts. The rest, water extracts of thirty four species (Cheongilppong (Morus alba L.) etc.) and 80% ethanol extracts of thirty four species (Wonjukojo (Morus alba L.) etc.) showed inhibitory activity (above 90%) on ACE. Also, to search of xanthine oxidase (XOase) inhibition were that water extracts of five species (Cheongsipjosaeng (Morus alba L.), Suwon 3 (Morus alba L.) etc.) and 80% ethanol extracts of Jeokmok (Morus alba L.) showed inhibitory activity (above 50%) on XOase. This result revealed, strong biological activity in spite of has a little total phenol contents. These water and 80% ethanol extracts from mulberry leaves (Morus alba L.) are expected good candidate for development into anti-hypertentive and anti-gout sources.

• Biomolecules & Therapeutics
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• v.1 no.2
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• pp.220-225
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• 1993

Effect of BR-900317 on the angiotensin I-induced pressor response in pithed rats and the effects of its single oral administration on plasma angiotensin converting enzyme (ACE) activities in normotensive rats and on the cardiovascular system in hypertensive model rats (SHR, RHR), were compared with those of captopril. BR-900317 attenuated the angiotensin I-induced pressor effects in pithed rats. In a single oral dose administration study, BR-900317 inhibited the plasma ACE activities in a dose-dependent fashion. Duration of the action of BR-900317 was similar to that of captopril. BR-900317 produced antihypertensive effect in spontaneously hypertensive rats and dose-dependent antihypertensive effect in 2-kidney Goldblatt hypertensive rats without affecting heart rate. These results suggest that the main mechanism of the antihypertensive effect of BR-900317 is the suppression of angiotensin II production due to the inhibition of the ACE.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.247-252
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• 2000

As functionality investigation of Korean traditional soybean fermentation foods, an antihypertensive peptide was separated during Chunggugjang fermentation by Bacillus subtilis CH-1023 and investigated inhibitory effect against angiotensin converting enzyme. After incubation at $20^{\circ}C,\;30^{\circ}C,\;40^{\circ}C,\;50^{\circ}C,\;60^{\circ}C$ for the $0{\sim}72$ hrs, protein content, protease activity and angiotensin converting enzyme inhibitory rate were determined. The protein content and protease activity were increased and reached maximum at 60 hrs fermentation with $40^{\circ}C$ and decreased after the 60 hrs fermentation. The optimum condition for antihypertensive peptide from Chunggugjang was appeared for 60 hrs at $40^{\circ}C$. Crude extract of Chunggugjang was partially purified by Amicon YM-3 membrane filtration and Sephadex G-10, G-25 gel filtration. The purified peptide showed inhibitory rate of 94.3% with 0.5 mg peptide content. The most prominent amino acid composition of the peptide from Chunggugjang was alanine, followed by phenylalanine, histidine.

• Journal of electromagnetic engineering and science
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• v.8 no.1
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• pp.17-22
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• 2008

It is presented that sampling rates for behavioral modeling of quasi-memory less nonlinear devices can be far less than the Nyquist rate of the input signal. Although it has been believed that the sampling rate of nonlinear device modeling should be at least the Nyquist rate of the output signal, this paper suggests that far less than the Nyquist rate of the input signal can be applied to the modeling of quasi-memoryless nonlinear devices, such as frequency multipliers. To verify, a QPSK signal at 820 MHz were applied to a frequency tripler, whereby the device can be utilized as an up-converting mixer into 2.46 GHz with the aid of digital predistortion. AM-AM, AM-PM and PM-PM can be successfully measured regardless of sampling rates.

• Journal of Satellite, Information and Communications
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• v.9 no.4
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• pp.13-15
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• 2014

At frequencies above 10 GHz, rain is a dominant propagation phenomenon on satellite link attenuation. The prediction of rain attenuation is based on the point rainfall rate for 0.01 % of an average year with one minute integration time. Most of available rain data have been measured with 60 minutes integration time, and many researchers have been studying on converting the rainfall rate data from various integration times to one minute integration time. This paper proposes a new Multiple Regression model for the conversion, and the proposed schemes show better performance than the existing schemes.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.2
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• pp.962-977
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• 2019

The human voice is a convenient method of information transfer between different objects such as between men, men and machine, between machines. The development of information and communication technology, the voice has been able to transfer farther than before. The way to communicate, it is to convert the voice to another form, transmit it, and then reconvert it back to sound. In such a communication process, a vocoder is a method of converting and re-converting a voice and sound. The CELP (Code-Excited Linear Prediction) type vocoder, one of the voice codecs, is adapted as a standard codec since it provides high quality sound even though its transmission speed is relatively low. The EVRC (Enhanced Variable Rate CODEC) and QCELP (Qualcomm Code-Excited Linear Prediction), variable bit rate vocoders, are used for mobile phones in 3G environment. For the real-time implementation of a vocoder, the reduction of sound quality is a typical problem. To improve the sound quality, that is important to know the size and shape of noise. In the existing sound quality improvement method, the voice activated is detected or used, or statistical methods are used by the large mount of data. However, there is a disadvantage in that no noise can be detected, when there is a continuous signal or when a change in noise is large.This paper focused on finding a better way to decrease the reduction of sound quality in lower bit transmission environments. Based on simulation results, this study proposed a preprocessor application that estimates the SNR (Signal to Noise Ratio) using the spectral SNR estimation method. The SNR estimation method adopted the IMBE (Improved Multi-Band Excitation) instead of using the SNR, which is a continuous speech signal. Finally, this application improves the quality of the vocoder by enhancing sound quality adaptively.