• Journal of Korea Foundry Society
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• v.11 no.4
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• pp.293-302
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• 1991

Aluminum alloy matrix composites reinforced with various amounts of $Al_2O_3$ short fibers have been produced by a combined technique of rheo-compocasting and hot extrusion. Distribution of fibers in the composites fabricated by rheo-compocasting was relatively uniform. A good degree of uniaxial fiber alignment has been achieved by hot extrusion, but a lot of fibers fractured during extrusion. The tendency of fiber fracturing increases as the aspect ratio and the amount of fibers increase. Relatively good bonding between fiber and matrix was obtained by the formation of $MgAl_2O_4$ and Mg(Al, Fe)$_2O_4$ at the interface between fiber and matrix. In extruded composites, fiber-strengthening effect was relatively small since a lot of fibers fractured during hot extrusion. On the other hand, dispersion strengthening effect may increase. In order to improve the fiber strengthening effect, it is important to optimize the extrusion condition with consideration of metal flow in extrusion die.

• Structural Engineering and Mechanics
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• v.39 no.6
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• pp.795-812
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• 2011

Estimation of damage probability of buildings under a future earthquake is an essential issue to ensure the seismic reliability. Fragility curves are useful tools for showing the probability of structural damage due to earthquakes as a function of ground motion indices. The purpose of this study is to compare the damage probability of R/C buildings with low and high level of strength and ductility through fragility analysis. Two different types of sample buildings have been considered which represent the building types mentioned above. The first one was designed according to TEC-2007 and the latter was designed according to TEC-1975. The pushover curves of sample buildings were obtained via pushover analyses. Using 60 ground motion records, nonlinear time-history analyses of equivalent single degree of freedom systems were performed using bilinear hysteretic model and peak-oriented hysteretic model with stiffness - strength deterioration for each scaled elastic spectral displacement. The damage measure is maximum inter-story drift ratio and each performance level considered in this study has an assumed limit value of damage measure. Discrete damage probabilities were calculated using statistical methods for each considered performance level and elastic spectral displacement. Consequently, continuous fragility curves have been constructed based on the lognormal distribution assumption. Furthermore, the effect of hysteresis model parameters on the damage probability is investigated.

• Economic and Environmental Geology
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• v.30 no.6
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• pp.531-541
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• 1997

Unconsolidated sediments of Youngjong Island were investigated to consider the vertical distribution of clay minerals and their origin. At least three sedimentation units can be recognized by color, magnetic susceptibility, and pH. X-ray diffraction analysis of clay size fraction reveals that illite is the most abundant phase (52.06%), and chlorite (27.16%), kaolinite (16.92%), smectite (3.86%) occur next to it. Detailed XRD study suggests that illitic materials contain fairly large amount of ordinary muscovite derived from the mica schist in Youngjong Island and adjacent area. The relative amount of kaolinite and chlorite is less than those of samples from estuary mouth of several rivers that flow to Yellow Sea and South Sea. Especially smectite content of the present sample is much higher than those of estuary sediments. These indicate that the unconsolidated sediments of tidal-flat deposit in Youngjong Island are largely affected by marine influence and partly affected by sediment in influx from China. However, some degree of source of this unconsolidated sediments is inland origin from adjacent estuary sediment and in situ or nearby weathered materials.

• Journal of Korean Biological Nursing Science
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• v.13 no.1
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• pp.37-43
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• 2011

Purpose: This study has been performed to identify the correlation between depression and physical fitness of the elderly women living in a rural area. Methods: The target people were chosen and visited on February, 2011. We could meet them at a community health center in Jeonnam. The questionnaire answered by 321 was conducted to figure out the degree of depression. Also, physical fitness using senior fitness test was measured. This study was analyzed using $x^2$ test, Fisher exact test, t-test and Pearson's correlation coefficient by SAS program. Results: It was analyzed that distribution of depression was 31.9%, and depression was correlated with upper flexibility (p<.001). There was no significant relation to physical fitness by depression except weight (p=.039) and back scratch (p=.007) as well. Conclusion: These results can not only contribute to understanding of the depression of the elderly women, but also suggest that depression prevention program is necessary for them.

• Journal of Korean Clinical Health Science
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• v.1 no.1
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• pp.9-17
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• 2013

Purpose. This study is to find the degree of variations and trends of hospital services utilization for hypertensive disease, and have done the comparative analysis of the factors affecting occurring some variations. For this, this study uses the data for patients-survey and health-survey of a regional society by Korea Institute for Heath and Social Affairs in 2008; The regional units are classified into 160 of medium size medical service areas. Methods. I understand the level of variation by using index of Extremal Quotient(EQ) and Coefficient Variation(CV), and analyze critical factors influencing some differences in hospital services utilization by using multi-regression model. Results. The main results are followed:The first, in case of rate of hospital services utilization according to standarization of sex and age by small area, I find the variations of EQ 5.3 and CV 0.3; In Ho-nam, especially, the variation of high rank of 10 of age shows higher distribution. The second, the results analyzing the factors influencing on hospital services utilization by multi regression model are that a number of bed hospitals is significant positive relationship and EQ-5D of health behavior is significant negative one. Conclusions. To increase equity of hospital services utilization for hypertensive disease, this study requests the appropriate supply management of bed hospitals by region, efficient allocation of resources, and revitalization of the health promotion program.

• Phonetics and Speech Sciences
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• v.4 no.3
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• pp.75-83
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• 2012

The aims of this study were three. First, to examine the degree of deviation from dictionary prescribed symbols and actual speech made by American English speakers. Second, to measure the frequency of vowel and consonant production of American English speakers. And third, to investigate gender differences in the segmental sounds in a speech corpus. The Buckeye Speech Corpus was recorded by forty American male and female subjects for one hour per subject. The vowels and consonants in both the phonemic and phonetic transcriptions were extracted from the original files of the corpus and their frequencies were obtained using codes of a free software R. Results were as follows: Firstly, the American English speakers produced a reduced number of vowels and consonants in daily conversation. The reduction rate from the dictionary transcriptions to the actual transcriptions was around 38.2%. Secondly, the American English speakers used more front high and back low vowels while three-fourths of the consonants accounted for stops, fricatives, and nasals. This indicates that the segmental inventory has nonlinear frequency distribution in the speech corpus. Thirdly, the two gender groups produced vowels and consonants similarly even though there were a few noticeable differences in their speech. From these results we propose that English teachers consider pronunciation education reflecting the actual speech sounds and that linguists find a way to establish unmarked segmentals from speech corpora.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.317-328
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• 2020

The board of directors play an important role in corporate climate strategy-making and decisions but might also compromise environmental policies to minimize agency cost. This study critically investigates the relationship between the attributes of the board of directors and the degree of sustainability performance for the energy sector as discussed in the literature. Our study cumulates existing knowledge offering important characteristics for a balanced board structure to increase the board's effectiveness in adopting sustainable initiatives that could reduce the adverse impact of an energy corporation's operation on the environment. Crucial attributes of the board of directors deemed to be positively associated with the commitment to reduce carbon footprint in the environment have been identified. Based on our extensive analysis of the literature we propose a conceptual framework that measures the influence of the board of directors' attributes on corporate environmental and social sustainability performance. The proposed framework will be useful as an initial step for top management and regulators to gain a better understanding of the balanced board structure required to achieve the social and environmental sustainability performance of corporations. Further, this paper contributes to a body of knowledge about how the board of directors could play a crucial role in monitoring social and environmental threats.

• Journal of Korean Academy of Nursing
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• v.23 no.2
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• pp.269-283
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• 1993

The purpose of this study was to develop a typology of stress in Nurses through the use of a Q methodology. The research was done between June, 1 and November 30,1992 Fifty nurse working in a hospital were interviewed to solicit statements on their opinions about concepts factors and coping methods related to stress. The statements which were collected were classified and categorized to a find list 48 statements. Each of the statements was written dr a separate card and 30 nurses were a shed to sort the co\ulcorner\ulcorner\ulcorner ac-cording the degree of agreement along with quasinormal distribution. The results of the sorting by each subject were coded and analyzed using the Quanal PC program. As a result of the analysis, four types were identified ; Type I was classified and named as ” neccessary for living Type II was named as ” stimulues to be avoided Type III was named as ” situation to be consumption. Type IV was named as ” self-limited problem which can be solve The correlation among each types was relatively high, but the characteristics of each type are unique and distinct. throughout this study, it was indentified that the type of Nurse’s stress would be formed.

• Journal of Korean Academy of Nursing
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• v.28 no.2
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• pp.392-402
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• 1998

By using Q-methodology, this study examines the attitudes of pregnant womens' husbands toward breastfeeding. Also, the research provides basic data necessary to develop a strategy for recommending breastfeeding. A total of 112 items for the Q-population were collected from related literature and interviews with the general public, specialists, pregnant women and their husbands. Finally, 38 statements were selected. Twenty one husbands of pregnant women classified these statements on each card on a 1 to 9 point scale(forced normal distribution) and wrote the reasons for both the most supported and the most resisted statements. The materials collected were analyzed by using pc QUANL program. The analysis drew down following fact that even though the attitudes of the husbands of pregnant were very similar, they could be classified to three types according to the motivation and recognition the degree of choosing breastfeeding. Type 1 is the mother's duty supporter, who insists that breastfeeding is completely natural and the proper duty of the mother. Type 2 is the emotional value supporter, who thinks that breastfeeding emotionally affects both the baby and the mother in a positive way. Type 3 is the conditional choice supporter, who chooses the most proper suckling way of feeding according to given conditions.

• Bulletin of the Korean Chemical Society
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• v.34 no.7
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• pp.2063-2066
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• 2013

While many eukaryotic and some prokaryotic proteins show a phosphorylation-dependent mobility shift (PDMS) on SDS-PAGE, the molecular mechanism for this phenomenon had not been elucidated. We have recently shown that the distribution of negatively charged amino acids around the phosphorylation site is important for the PDMS of some proteins. Here, we show that replacement of the phosphorylation site with a negatively charged amino acid results in a similar degree of the mobility shift of a protein as phosphorylation, indicating that the PDMS is due to the introduction of a negative charge by phosphorylation. Compared with a protein showing no shift, one showing a retarded mobility on SDS-PAGE had a decreased capacity for SDS binding. The elucidation of the consensus sequence (${\Theta}X_{1-3}{\Theta}X_{1-3}{\Theta}$, where ${\Theta}$ corresponds to an acidic function) for a PDMS suggests a general strategy for mutagenizing a phosphorylatable protein resulting in a PDMS.