• Journal of Mechanical Science and Technology
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• v.16 no.11
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• pp.1435-1439
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• 2002

This paper presents a form of the cohesive surface separation potential, which can produce potential curves by varying a single dimensionless parameter. Results show that a partial modification of Xu and Needleman's (1994) cohesive surface separation potential makes it possible to present the other potential corves as a special case as long as the normal separation is concerned. The proposed potential may describe interfacial debonding-crack initiation and growth-character of materials and, through numerical simulation, provide an insight for the effect of different cohesive surface separation potentials on the interfacial debonding.

• Journal of Integrative Natural Science
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• v.8 no.2
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• pp.111-116
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• 2015

Liquid chromatographic enantiomer separation of ${\alpha}$-amino acid esters as nitrobenzoxadiazole (NBD) derivatives was performed using several chiral stationary phases (CSPs) based on polysaccharide derivatives under fluorescence detection. For enantiomer separation by normal HPLC, the non-aqueous derivatization method of ${\alpha}$-amino acid esters for NBD analytes was introduced. Among the six CSPs used in this study, the performance of Chiralpak IA was superior for enantiomer resolution of NBD derivatives of several ${\alpha}$-amino acid methyl esters. Also the convenient analytical method using polysaccharide-derived CSPs developed in this study was applied to determine the optical purity of ${\alpha}$-amino acids esters. It was investigated that the enantiomeric impurity levels of 0.02-1.73% were found after determination of enantiomeric purities of several commercially available L-amino acid methyl esters. It is expected to be quite useful for enantiomer separation of other ${\alpha}$-amino acid esters as NBD derivatives by normal HPLC.

• The Journal of Pediatrics of Korean Medicine
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• v.18 no.1
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• pp.63-75
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• 2004

Objective: Atopic dermatitis has a close relationship with degranulation of mast cell and separation of histamine. As there was no experiment with herb, using Lithospermum erythrorhizon, We investigated experimental influence of Lithospermum erythrorhizon on degranulation of mast cell and separation of histamine in Sprague-Dawley rats. Methods: The SD rats were classified into three groups. One group was a normal one treated by normal saline before medical treatment. The other was a control group prescribed to Compound 48/80 before normal saline treatment. And the third was a expenimental group prescribed to compound 48/80 after medical treatment of Lithospermum erythrorhizon. Then, We investigated the experimental results by measuring the degree of degranulation and separation of histamine. Results: Lithospermum erythrorhizon did obviously inhibit the degree of degranulation of mast cell(p<0.05). Lithospermum erythrorhizon inhibited the separation of histamine in the plasma. Conclusion: Lithospermum erythrorhizon may be one of the effective therapeutic regimens on atopic dermatitis.

• The Journal of Pediatrics of Korean Medicine
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• v.18 no.2
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• pp.107-117
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• 2004

Objective : Atopic dermatitis has a close relationship with degranulation of mast cell and separation of Histamine. As there's no experiment with herb, using Arctii Fructus, we investigated experimental influence of Arctii Fructus on degranulation of mast cell and separation of histamine in SD rat. Methods : The SD rats are classified into three groups. One group is normal one treated by normal saline before medical treatment. The other is control group prescribed to Compound 48/80 before normal saline treatment. And the third is experimental group prescribed to compound 48/80 after medical treatment of Arctii Fructus. Then, I investigated the experimental results by measuring the degree of degranulation and separation of histamine. The results of investigation on SD rat group showing the degree of inhibitory effect of degranulation of a mast cell are as follow, the normal group treated by normal saline reflecting the degree of degranulation is $6.10{\pm}0.20\;%$, the control group treated by only compound 48/80 is $87.56{\pm}11.00\;%$, the experimental group which treated by compound 48/80 and Arctii Fructus's medical treatment is $16.26{\pm}4.67\;%$. Results : The normal group treated by only normal saline reflecting the degree of degranulation is $6.10{\pm}0.20\;%$, the control group treated by only compound 48/80 is 87.56=11.00 %, the experimental group treated by compound 48/80 and Arctii Fructus's medical treatment is $16.26{\pm}4.67\;%$. This result indicates that the degree of degranulation of mast cell is obviously inhibited (p<0.0l) in the experimental group in comparison with control one. The analysis of data obtained from plasma, which collected from the experimented SDrats' hearts before their death, and the measurement of quantity of histamine secretion show the following results. The quantity of normal group and control one is $25.34{\pm}4.58$ nM, $348.59{\pm}30.77$ nM respectively, and experimental one prescribed to compound 48/80 after medical treatment of Arctii Fructus is $263.56{\pm}21.34$ nM. This result indicates that separation of histamine isobviously inhibited in the experimental group in comparison with control one (p<0.05). Conclusions : Arctii Fructus does obviously inhibit the degree of degranulation of mast cell (p<0.0l) and separation of histamine in the plasma (p<0.05).

• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.373-379
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• 2018

A transparent, freestanding Porous Aromatic Framework-97 (PAF-97) membrane was successfully synthesized via a one-step acid-catalyzed reaction. Due to the introduction of ether groups, the obtained PAF-97 membrane possesses enhanced structural flexibility, thus increasing the flexibility of the resulting membrane. This is proofed by the fact that the feeding pressure of the membrane reaches as high as 5.5 bar during the separation of gas mixtures. The Young's moduli of the membrane were 6.615 GPa and 11.11 GPa, either in a dry or hydrated state respectively. To be highlighted, under a feeding pressure of 3.6 bar, the PAF-97 membrane rendered the permeance values of $2.90{\times}10^{-7}$, $1.29{\times}10^{-8}mol\;m^{-2}s^{-1}Pa^{-1}$ for $CO_2$ and $CH_4$, respectively, with a $CO_2/CH_4$ permselectivity of 22.48.

• Water for future
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• v.26 no.4
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• pp.73-83
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• 1993

This study focuses on the separation effect analysis of rainfall data for 2-parameter log-normal, 3-parameter log-normal, type-extreme value, 2-parameter gamma, 3-parameter gamma, log-Pearson type-III, and general extreme value distribution functions. Difference in the relationship between the mean and standard deviation of skewness for historical data and relations derived from 7 distribution functions are analyzed suing the Monte Carlo experiment. The results show that rainfall data has the separation effect for 6 distribution functions except 3-parameter gamma distribution function.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.2
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• pp.237-245
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• 2012

This paper describes an acoustic echo canceller with double-talk by the blind signal separation. The acoustic echo canceller is deteriorated or diverged in the double-talk period. So we use the blind signal separation to estimate the near-end speech signal and to eliminate the estimated signal from the residual signal. The blind signal separation extracts the near-end signal with dual microphones by the iterative computations using the 2nd order statistical character. Because the mixture model of blind signal separation is multi-channel in the closed reverberation environment, we used the copied coefficients of echo canceller without computing the separation coefficients. By this method, the acoustic echo canceller operates irrespective of double-talking. We verified performances of the proposed acoustic echo canceller by simulations. The results show that the acoustic echo canceller with this algorithm detects the double-talk periods thoroughly, and then operates stably in the normal state without the divergence of coefficients after ending the double-talking. And it shows the ERLE of averagely 20dB higher than the normal LMS algorithm.

• Proceedings of the KSPS conference
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• 2003.10a
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• pp.25-28
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• 2003

The aim of this paper is to analyze the pathological voice by separating signal into periodic and aperiodic part. Separation was peformed recursively from the residual signal of voice signal. Based on initial estimation of aperiodic part of spectrum, aperiodic part is decided from the extrapolation method. Periodic part is decided by subtracting aperiodic part from the original spectrum. A parameter HNR is derived based on the separation. Parameter value statistics are compared with those of Jitter and Shimmer for normal, benign and malignant cases.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.48
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• pp.233-240
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• 1998

Recently, Hong-Jun Kim et al. introduced an improved process incapability index $C^*_{psk}$ by the transformation of the $C_{psk}{\;}C^*_{psk}$. A simple transformation of $C_{psk}$, can be regard as a process incapability index, provides an uncontaminated separation between information concerning the process accuracy and precision while this kind of information separation is not available with the $C_{psk}$. By an identical conception, in this article a new process incapability index $C^*_{psk}$ for Non-Normal process can be proposed by the transformation of the process capability index $C^*_{psk}$. The motivation behind introduction of $C^*_{psk}$ is that process capability index $C^*_{psk}$ cannot give information of the process accuracy and precision. A significant result of this research that $C^*_{psk}$ for the case where the target value T is equal to the midpoint of the specification limits or not Is evaluated without respect to T. Accordingly, $C^*_({psk})$ will be propose a reasonable process incapability measure for Non-Normal process

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.9
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• pp.2245-2250
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• 1994

The normal coordinates of a nonclassically damped systems are coupled by nonzero off-diagonal elements of modal damping matrix. The relationship between modal coupling and the frequency separation of the natural modes is presented in this paper. Contrary to widely accepted beliefs, increasing the frequency separation of the natural modes does not neccessarily diminish the effect of modal coupling. Consequently, in the pratical engineering applications, wide frequency separation of the natural modes would not be sufficient for neglecting modal coupling.