• Steel and Composite Structures
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• v.24 no.5
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• pp.579-589
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• 2017

The objective of this work is to analyze post-buckling of functionally graded (FG) beams with porosity effect under compression load. Material properties of the beam change in the thickness direction according to power-law distributions with different porosity models. It is known that post-buckling problems are geometrically nonlinear problems. In the nonlinear kinematic model of the beam, total Lagrangian finite element model of two dimensional (2-D) continuum is used in conjunction with the Newton-Raphson method. In the study, the effects of material distribution, porosity parameters, compression loads on the post-buckling behavior of FG beams are investigated and discussed with porosity effects. Also, the effects of the different porosity models on the FG beams are investigated in post-buckling case.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.279-284
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• 2000

The bridge is nation's principal structure and its influence for national economy is enormous. But it is essential for maintenance of deteriorated bridge because of the increased service life and the decreased performance. For the bridge reinforced by continuos slabs and post-tensioning, we evaluate th stress properties of girders and internal support. Results are almost coincidence between measured data in the field and analysed data by computer. We compared the effects by successive order of post- tensioning and order considered distribution of each girder's camber and stress. Bridge's camber and stress showed respectively symmetry and asymmetry shape by post tensioning order. For the effect of post-tensioning force partition, we divided the post-tensioning force into 3 types (100%, 20%, 30%), and the results show t도 difference of final stress and camber.

• The Korean Journal of Nuclear Medicine
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• v.35 no.6
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• pp.343-351
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• 2001

Cerebral post-ischemic hyperperfusion has been observed at the acute and subacute periods of ischemic stroke. In the animal stroke model, early post-ischemic hyperperfusion is the mark of recanalization of the occluded artery with reperfusion. In the PET studios of both humans and experimental animals, early post-ischemic hyperperfusion is not a key factor in the development of tissue infarction and indicates the spontaneous reperfusion of the ischemic brain tissue without late infarction or with small infarction. But late post-ischemic hyperperfusion shows the worse prognosis with reperfusion injury associated with brain tissue necrosis. Early post-ischemic hyperperfusion defined by PET and SPECT may be useful in predicting the prognosis of ischemic stroke and the effect of thrombolytic therapy.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.5
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• pp.91-96
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• 2018

The oleophobic property of surfaces modified with micro-post structures are investigated for a range of micro-post diameter ($11-23{\mu}m$) and pitch ($20-40{\mu}m$). The contact angle of an oil droplet on surfaces with various micro-post dimensions was calculated using the Cassie-Baxter model and did not show a good agreement with the measured contact angle. From measurement, the micro-post with diameter of $23{\mu}m$ and pitch of $32{\mu}m$ was found to have the highest contact angle ($134.3^{\circ}$).

• The Korean Journal of Health Service Management
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• v.12 no.1
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• pp.137-147
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• 2018

Objectives : The purpose of this study was to identify the post-traumatic stress, social support, and depression of Vietnam veterans and the effects of post-traumatic stress and social support on depression. Methods : This study was carried out from June 2017 to September 2017 with the cooperation of the Korean Society of Veterans' Affairs and 250 Vietnamese veterans from D city were randomly sampled and collected. The collected data were used by SPSS 24.0 Statistics Program. Results : Social support was inversely correlated with post-traumatic stress (r=-.268, p<.001) and depression (r=-.333, p<.001), and post-traumatic stress and depression (r=.592, p<.001) were positively correlated. Post-traumatic stress and social support of veterans had a significant effect on depression, and post-traumatic stress and social support showed an explanatory power of 37.7% in depression. Conclusions : It is necessary to improve soldiers' mental health by mediating their post-traumatic stress and reducing their depression level by establishing a social support system.

• The Journal of Korea CHUNA Manual Medicine
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• v.1 no.1
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• pp.45-53
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• 2000

Objectives : CHUNA therapy that removes compression of dislocated vertebral bones has positive effect, but sometimes improper CHUNA manual therapy may give rise to negative effect. The aim of this study is to make sure that cervical CHUNA manual therapy give positive effect or negative effect to the blood flow velocity of vertebral artery(VA) and basilar artery(BA) by Trancranial Doppler sonography(TCD). Methods : We performed TCD study on 20patients(male 5, female 15, mean ages 38.5 years) with diagnosis like cervical movement related disorder, headache or dizziness. After we measured mean blood flow velocity(Vm) of VA and BA before cervical CHUNA therapy(Pre-CCT) and after cervical CHUNA therapy(Post-CCT), statistically evaluated the results. Results: The patients received cervical CHUNA therapy for TA sequel, HIVD of cervical spine, headache, dizziness, neck stiffness etc. VA Vm was $31.9{\pm}8.0cm/sec$ before CHUNA therapy, but significantly increased $35.0{\pm}8.7cm/sec$ after CHUNA therapy (p < 0.05). But, there was no significant variation of BA Vm between $41.8{\pm}7.5cm/sec$ Pre-CCT and $41.2{\pm}8.5cm/sec$ Post-CCT(p>0.05). Though VA Vm slightly increased after CHUNA therapy in normal range group, there was no significant variation between VA Vm Pre-CCT and VA Vm Post~CCT. In VA Vm decrease group, VA Vm significantly increased after CHUNA therapy(p<0.05). But, there was no significant variation of BA Vm between Pre-CCT and Post-CCT in BA Vm normal range group and BA Vm decrease group(p>0.05). Conclusions: These findings suggest that cervical CHUNA manual therapy have positive effect on blood flow velocity of VA and BA.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.6 no.1
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• pp.15-26
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• 2000

Purpose : This study was done to examine the actual effect of the scapular position in these flexibility tests. The purpose of this study was to examine the differences between the measurement of SRT(Sit-and-Reach Test) without intentional abduction of the scapular (pre-test) and with intentional abduction of the scapular (post-test). The hypothesis is: 1. There is no differences in the SRT result of the pre-test and the post-test. 2. There is no differences in the HJA(Hip Joint Angle) result of the pre-test and the post-test. 3. There is no differences in the Spine Motion Test(SMT) result of the pre-test and the post-test. Method : The total 60 people (30 men, 30 women) were participated in this study. In the pre-test, the subjects were asked to sit on the examination table and try the SRT motion; and then the HJA, SRT and the SMT numerical values were taken. In the post-test. the subjects were instructed to intentionally bring the scapula outward from the midline; and the HJA, SRT and the SMT numerical values were taken. Result : In the pre-test. the SRT result averaged 34.17cm. and in the post-test. the SRT result averaged 36.68cm. The difference was about 2.81cm which showed a significant mean statistically (p<0.01). The measurement increased by 8.22%. The HJA was $85.9^{\circ}$ in pre-test, and it was $85.5^{\circ}$ in post-test. giving the $0.4^{\circ}$ differences. Therefore, it didn't have a statistical mean (p>0.05). The SMT value was 69.56cm in the pre-test. and it was 69.28cm in the post-test, about 0.28cm decreased. Therefore, it didn't have a statistical mean (p>0.05). SRT values and HJA values were correlated (p<0.01). SMT values and SRT values (p<0.01), and SMT values and HJA values(p<0.05) were each in counter correlation. Conclusion : The result of the SRT without intentional scapular abduction (34.17cm) and with intentional scapular abduction (36.68cm) showed a significant increase about 8.22% (p<0.01). In SRT, the effect of the intentional scapular abduction on SMT showed no significant means, the pretest value being 69.56cm and the post-test value being 69.28cm (p>0.05).

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.1
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• pp.50-55
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• 2008

AI-doped ZnO(AZO) thin films have been fabricated on glass substrate by sol-gel method, and the effect of Al precursors and post-annealing temperature on the characteristics of AZO thin films was investigated. The sol was prepared with zinc acetate, EtOH, MEA and Al precursors. In order to dope Al in ZnO, two types of aluminum nitrate and aluminum chloride were used as Al precursor. Zinc concentration was 0.5 mol/l and the content of Al precursor was 1 at% of Zn in the sol. The sol was spin-coated on glass substrate, and the coated films were annealed at 550ue for 2 hand were post-annealed at temperature ranges of $300{\sim}500^{\circ}C$ for 2 h in reducing atmosphere ($N_2/H_2$= 9/1). Structural, electrical and optical propertis of the fabricated AZO thin films were analyzed by XRD, FE-SEM, AFM, hall effect measurement system and UV-visible spectroscopy. Optical and electrical properties of AZO thin films prepared with aluminum nitrate as Al precursor were better than those of films prepared with aluminum chloride. The electrical resistivity and the optical transmittance of films decreased with increasing post-annealing temperatures. The minimum electrical resistivity of $2{\times}10^{-3}$ and the maximum optical transmittance of 91% were obtained for the AZO thin films post-annealed at $550^{\circ}C\;and\;300^{\circ}C$, respectively.

• The Journal of Industrial Distribution & Business
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• v.12 no.11
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• pp.17-31
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• 2021

Purpose: Despite the fact that face (i.e. Chemyon) is deeply-rooted in Korean culture and significantly affects the behavior of Korean people, the effect of face on leisure consumers' consumption behavior has only reported mixed findings, that is, significant and/or insignificant face effects have been reported. It is necessary to integrate prior research findings, and comprehensively examine the effect of face on leisure consumers' consumption behavior. The purpose of this study was to investigate the effect (i.e. effect size, and moderating variables) of face on leisure consumers' consumption behavior through meta-analysis. Research design, data and methodology: Among 1,019 face-related academic studies, retrieved from the academic research information services (RISS), 34 studies and 300 cases examining the effect of face on leisure consumers' consumption behavior were finally included for meta-analysis. Face measured as face sensitivity and/or a face sensitivity sub-component (shame-consciousness, formality-consciousness, and other-consciousness) were integrated in the meta-analysis. Leisure consumers' consumption behavior was classified as antecedents of purchase (overall conspicuous consumption tendency, overall symbolic consumption tendency, personality, high price, high quality, brand seeking, fashion seeking, enjoyment, other person (interpersonal) consideration, position, reference group, and attitude), purchase (purchase intention, unplanned purchase, purchase, and expenditure), and post-purchase (satisfaction, repurchase, and post-purchase). The data used in the meta-analysis was comprised of correlation coefficients, and the meta-analysis was performed using the R-program. Results: The overall mean effect size of face on leisure consumers' consumption behavior was .248. It was found that the effect size was the largest in the order of shame-consciousness face, formality-consciousness face, and other-consciousness face. Among the types of leisure consumers' consumption behavior categorized as dependent variables, the effect size was found to be largest in the order of position, attitude, reference group, post-purchase behavior, brand seeking, personality, trend seeking, etc. In addition, it was found that the leisure types moderated the effect size of face on leisure consumers' consumption behavior. The effect size was found to be largest in the order of skin diving, baseball, various leisure participation, dance, gambling, golf, etc. Conclusions: Face moderately or significantly influence leisure consumers' consumption behavior.

• Journal of The Korean Association For Science Education
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• v.32 no.6
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• pp.1027-1038
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• 2012

We investigated the effect of Science Writing Heuristic (SWH) on elementary students' concept formation and their retention. Also we explored the interaction effect of those with scientific attitudes. We developed mirrors/lenses lessons incorporating SWH. An experimental group of fifth grade students (n=25) had been instructed with SWH lessons for six periods while a control group (n=25) taught according to the normal science lessons based on the Korean national curriculum using teacher's guides published by the Ministry of Education. Results of pre- and post-test of understanding the concept of mirrors and lenses showed a positive impact of SWH on both male and female students. However, the retention effect after post-test revealed that SWH only had an effect on female students' scientific attitudes. SWH, therefore, could be an effective teaching approach especially on concept formation, retention effects by fostering female students' scientific attitudes.