• 펄프종이기술
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• 제44권2호
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• pp.8-17
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• 2012

Three kinds of cationic acrylamide copolymer with different branch degree were prepared controlling the dosage of N, N'-methylenebisacrylamide. The physical characteristics of the branch-degree-modified copolymers were analyzed by intrinsic viscosity and charge density. The branch degree measurements were investigated by applying the colloidal titration phenomena using a spectrophotometer and comparison with the cationic regain measurement method. The results showed that the absorbance behaviors of spectrophotometer were distinctively different with the branch degree of copolymers. Also, the branch degree determinations and molecular structure estimations of the copolymers were numerically measured by applying the titration phenomena using a spectrophotometer. Finally, three kinds of branch-degree-modified copolymers were applied to flocculation test using arbocel micro pulp for the determination of flocculation behavior by different morphology of cationic acrylamide copolymers.

• 말소리와 음성과학
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• 제13권2호
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• pp.37-44
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• 2021

Preliminary findings are reported from five experiments testing the perceived naturalness of word tokens whose vowel durations are altered. The stimuli were minimal pairs of English words ending in a voiced/voiceless plosive. Results show an asymmetric effect of shortening and lengthening of the vowel on the perceived naturalness of the word. Incremental shortening of vowel duration initially shows a stable degree of perceived naturalness but rapidly deteriorates beyond a certain point. On the contrary, only a small degree of lengthening of the vowel made the perceived naturalness of the word quickly decay, but there was a floor effect such that the perceived degree of naturalness does not lower beyond a certain level. Further, the tokens with the original vowel duration were not always scored higher than the stimuli with a small degree of shortening. Future studies should address the issue of speaking rate and the ratio between the vowel and the stop closure duration to better understand the phenomenon. The issue investigated here has implications on the role of prototypical exemplars in the perception of phonotactic naturalness.

• 펄프종이기술
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• 제30권2호
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• pp.30-39
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• 1998

Effect of cationic starches and anionic colloidal silica on retention and drainage characteristics of Compozil system was investigated. Depending upon the degree of substitution and molecular weight of cationic starches and morphological characteristics of anionic colloidal silica, retention and drainage properties of Compozil system were significantly influenced. When cationic starch addition level increased above a certain limit retention and stock freeness were decreased. To elucidate this an electrostatic coagulation mechanism occurring between unadsorbed starch molecules and anionic colloidal silica was proposed. Unstructured colloidal silica showed greater improvement in retention than structured colloidal silica. Cationic corn starches with different degree of substitution and molecular weights were prepared and their effect as a constituent of Compozil system was also evaluated. By controlling the molecular weight and degree of substitution of cationic corn starch it was possible to achieve significant improvement in fines retention. Cationic corn starch with higher degree of substitution maintained its retention efficiency even when the stock conductivity was increased. Turbidity measurement technique was found to be a simple and useful method to measure the retention characteristics.

• 한국주조공학회지
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• 제3권3호
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• pp.159-166
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• 1983

In order to develope domestic carburizers, the experiment was carried out by applying crystallization heat treatment to domestic anthracites and also to foreign products to compare with domestic anthracites.The present work was mainly concerned with the effect of their degree of crystallization of carbon-bearing materials on carbon pick-up in molten iron.Those effects were evaluated by the measurement of density, chemical composition, specific electric resistivity, and X-ray intensity of carbon-bearing materials. Experimental results thus obtained were summurized as follows. 1. The degree of crystallization of domestic anthracites and foreign products was increased with increasing heat treatment temperature. 2. The more degree of crystallization, the shorter the dissolving time of domestic anthracites in molten iron was obtained, while that of foreign products was remained constant. 3. As the degree of crystallization of domestic anthracites and foreign products was increased, the carbon content as well as carbon recovery in molten iron was increased.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.621-626
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• 2002

Two problems in the measurement of 6-DOF head vibration in very low frequency range were investigated in this study. One is how much error was involved in the estimation of three rotational and three translational motion at any specified point from measured 6 translational accelerations. The other is quantitative and qualitative influence of gravity on DC and AC component of the estimated accelerations in 6 degree of freedom, which were derived from pick-ups fixed on a helmet. In the study the effect of nonlinear terms on the estimation of 6 degree of freedom accelerations was negligible but gravity effect must be considered carefully.

• 설비공학논문집
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• 제13권1호
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• pp.25-29
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• 2001

A study has been conducted to investigate the effect of the heat transfer surface position in the range of dropwise condensation, filmwise condensation, and glacial condensation. For dropwise condensation promoter, the heat transfer surface was evaporated by gold. As a result, heat transfer rate is almost same where the position of heat transfer surface is between 45 and 135 degree. It is found that heat transfer rate was reduced as subcooled degree was increased. And it is also found that if the subcooled degree becomes lower, the position of heat transfer surface is more effective. Adversely, if the subcooled degree becomes higher, the effectiveness of surface position is getting relatively lower. Regardless of the position, the transition temperatures from dropwise condensation to filmwise condensation is in the vicinity of 80K.

• International Journal of Control, Automation, and Systems
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• 제1권4호
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• pp.401-411
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• 2003

Important results about two-degree-of-freedom PID controllers are surveyed for the tutorial purpose, including equivalent transformations, various explanations about the effect of the two-degree-of-freedom structure, relation to the preceded-derivative PID and the I-PD controllers, and an optimal tuning method.

• 보건행정학회지
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• 제8권2호
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• pp.149-165
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• 1998

The purpose of this study is to examine the effect of the health status on the quality of life of the rural elderly, and to examine the conditional effect of socialsupport for that influence. 'Quality of life' used in this study was defined by unidimensional approach. The data were collected by conducting individual interviews with 296 rural elderly people aged 60 and the above who were living in one township of Kangwondo, between the time period of October and November 1995. The main findings are as follows: 1. Hierarchical regression analyses were carried out to examine the relative contribution of three set of variables on the quality of life. The first step, which included sociodemographic factors showed that the coefficient of determination (R$^{2}$) was 8% and income was a statisically significant variable. The second step, by adding health related factors, revealed that the R$^{2}$ was increased to 34% by 26% point and the degree of health recognition was the statistically significant variable. The third step, by projecting additionall social support related variables revealed that the R$^{2}$ was 42% 2. The conditional effect of social support was analyzed to examine the influence the health status has on the quality of life. The results are as follows: 1) The IADL and the degree of social contact interacted, resulting in that the higher degree of social contact boosted the stronger effect of IADL. 2) The effect of subjective health recognition on the quality of life is depended upon degree of family ontact. 3) The effect of eyesight on the quality of life is depended upon degree of satisfaction in social relation. The lower the degree of social support was, the bigger the influence of health related variables affecting quality of life became. This study explains that health status is a major factor in predicting the quality of life of the aged. Particularly the subjective health recognition was an important factor as the perception of quality of life.

• 한국병원경영학회지
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• 제12권3호
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• pp.68-95
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• 2007

This research is designed for studying between transformational leadership and behavior of subordinate. We took a practical analysis with conception of leader acceptance to search function between transformational leadership and self-efficacy. For practical proof of this research, we look hypothetical inspection with collected data after posing a question with medical Staff of 459. The practical analysis of this research is as below. First, We could know that transformational leadership affect partially positive effect to self-efficacy of subordinate. That is, as a result for researching into the influence of subordinate to self-efficacy, setting each element which forms transformational leadership as hypotheses, charismatic behavior and intellectual stimulation of leader's have an positive effect on self-efficacy of subordinate. However, there is no relation between individualized consideration and self-efficacy of subordinate. Second, we analyzed effect of subordinate's acceptance of leader between transformational leadership and acceptance degree of leader, we could know that all of them which is Two subordinate purpose of transformational leadership have a controling effects as there must be existed differences on self-efficacy before and after interaction. It is also another suggestion of this research to provide a clue to next research which is related with the importance of acceptance and it, conception, because we find the fact there could be existed the difference according to acceptance degree of leader.

• 대한기계학회논문집A
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• 제20권7호
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• pp.2108-2117
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• 1996

The purpose of this paper is to investigate the influence of the exciter attached for the measurement of natural frequencies when extracting the frequency response functions of the test structure in experimental modal analysis. The procedure is first to model the attached exciter as an additional degree of freedom system and next to verify the suggested model by experimentally extracting the natural frequencies of the test structure with various values of exciter mass, stinger stiffness and attachment position of the exciter on the test structure. It is concluded that as additional degree of freedom system which includes the natural frequency of the exciter itself and axial stiffness of stinger should be considered to quantatively define the coupling effects of structure-exciter interaction on the measured natural frequencies. It is not the mass of the exciter itself but the coupling effect of the additional degree of freedom mass-spring system consisting of exciter body and armature coil that characterizes the natural frequency deviation. Therefore, when the natural frequency of this additional mass-spring system is outside of the test frequency range, the coupling effect of structure-exciter interaction can be minimized.