• Asia pacific journal of information systems
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• v.16 no.4
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• pp.179-202
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• 2006

The objective of this study is to identify the impacts of communication reinforcement on performance of learning in Web-PBL. Communication reinforcement is defined as the combination of information sharing and co-construction. As factors facilitating communication reinforcement, we propose learner's characteristics, task characteristics, and group characteristics. Learner's characteristics are collaboration-orientation, openness, holistic approach, and online community-orientation which reflects e-learning environment. Collaboration-oriented tasks as group projects were developed and given to groups with 5-6 members. The group characteristics are categorized into 'horizontal' and 'vertical', according to the patterns of communication between a group leader and members. To verify empirically the proposed research model, an experimental design was performed to learners who took on-line and off-line courses with group projects. We found important results as follows; First, field dependence has positive impacts on information sharing, and online community-orientation has positive impacts on co-construction. These results correspond with prior studies on relationship between field dependence and collaborative learning. Second, collaboration-oriented task directly impacts on information sharing, and indirectly affects co-construction, This result implicates that information sharing is pre-requisite of co-construction. Third, 'horizontal' was identified as a factor giving positive effects on information sharing and co-construction. This result implies that horizontal communication is very important to facilitate communication reinforcement.

• Advanced Composite Materials
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• v.18 no.3
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• pp.265-285
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• 2009

Off-axis compressive deformation behavior of a unidirectional CFRP laminate at high temperature and its strain-rate dependence in a quasi-static range are examined for various fiber orientations. By comparing the off-axis compressive and tensile behaviors at an equal strain rate, the effect of different loading modes on the flow stress level, rate-dependence and nonlinearity of the off-axis inelastic deformation is elucidated. The experimental results indicate that the compressive flow stress levels for relatively larger off-axis angles of $30^{\circ}$, $45^{\circ}$ and $90^{\circ}$ are about 50 percent larger than in tension for the same fiber orientations, respectively. The nonlinear deformations under off-axis tensile and compressive loading conditions exhibit significant strain-rate dependence. Similar features are observed in the fiber-orientation dependence of the off-axis flow stress levels under tension and compression and in the off-axis flow stress differential in tension and compression, regardless of the strain rate. A phenomenological theory of viscoplasticity is then developed which can describe the tension-compression asymmetry as well as the rate dependence, nonlinearity and fiber orientation dependence of the off-axis tensile and compressive behaviors of unidirectional composites in a unified manner. It is demonstrated by comparing with experimental results that the proposed viscoplastic constitutive model can be applied with reasonable accuracy to predict the different, nonlinear and rate-dependent behaviors of the unidirectional composite under off-axis tensile and compressive loading conditions.

• Fibers and Polymers
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• v.6 no.3
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• pp.206-218
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• 2005

Structural studies of series of 'as spun' and drawn PEEK fibers have been carried out using X-ray diffraction and optical microscopy techniques. The analysis of results suggest that fibers produced at a constant draw ratio with increasing draw temperatures show enhanced orientation and crystalline behaviour. The resolved equatorial and meridional traces provide additional structural parameters in terms of crystallinity, crystallite size, and crystallite thickness. It is concluded that drawing at a temperature below $T_g(i.e.,\;144^{\circ}C)$ results in poorly oriented non-crystalline materials, whereas drawing above $T_g$ results in highly oriented semi crystalline materials. Additional drawing proved to increase the overall orientation with slight improvements in lateral order of the chain molecules. Quantitative analysis revealed that the crystallite size increases with increasing drawing temperature. The results also revealed the increased crystallite size upon additional drawing. Crystalline orientation parameter, $_c$, suggests almost perfect orientation. In all cases, the amorphous orientation is found to be lower than the overall orientation parameter obtained from the optical birefringence. As a result of additional drawing, crystalline orientation was found to increase slightly but the increase in the orientation of non-crystalline material was found to be substantial. An average crystalline density was determined from the orthorhombic unit cell dimensions. It was found to vary as a result of processing conditions. It was also found that the value of the maximum birefringence shows heavy dependence on the chain conformation.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.05a
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• pp.320.2-320.2
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• 2004

• Journal of Convergence for Information Technology
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• v.9 no.4
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• pp.100-108
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• 2019

The purpose of this study is to analyze the influence of university students' dependence on smart-phone on career attitude maturity and the mediating effect of interpersonal problem in the analysis path. For this purpose, the study implemented a survey on students of universities in Seoul and Gyeonggi-do area and carry out a structural equation for empirical verification with a total of 218 copies. As a result, first, high level of daily life disturbance and virtual world orientation of university students, have a positive effect on interpersonal problems. Second, high level of daily life disturbance and virtual world orientation of university students, have a negative effect on career attitude maturity. Third, interpersonal problems of college students had a negative effect on career attitude maturity, and they were found to be fully mediated in relation to smart-phone dependence and career attitude maturity. Therefore, this study suggests that it can be used as a basic data for the development and application of various programs promoting the career attitude maturity of university students.

• Korean Journal of Health Education and Promotion
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• v.12 no.2
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• pp.146-161
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• 1995

This study is an effort to bring our attention to social dependence on alcohol, focusing on previous studies of drinking behaviors. Although drinking behavior and problems must be understood in a biopsychosocial framework, a certain aspect is often ignored in alcohol research. A few attention has been paid to social aspect of alcohol abuse or dependence. Social processes of drinking behavior deserve to have same attention as other aspects, psychological and physical aspects of the behavior. Literature show that the interdependence among group members exists to regulate individual's drinking behavior. Such social interactions tend to control drinking level for individual in terms of amounts, frequency, and preference. The drinking level tends to be dependent on desires for heavy drinkers, ignoring variabilities of individual's sensitivity to alcohol. However, such a heavy-oriented tendency in drinking behavior may have different patterns which are function of normative orientation of alcohol. negotiation among group members, and ethnoreligious characteristics. Perspectives from conflict tradition and symbolic interactionism are welcomed to illuminate multi-dimentional aspects of social dependence. Policy implication were discussed from public health perspective.

• Journal of the Korean Society of Clothing and Textiles
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• v.29 no.5 s.142
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• pp.715-726
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• 2005

The purpose of this study was to identify the effects of the sensation seeking and body image on female adolescents' clothing behavior and hair style attitude. The data was collected from 390 high school girls living in Seoul, via a self·administered questionnaires, and were analyzed by frequency, factor analysis, reliability test, Pearson's correlation, and multiple regression. The results of this study was as follows : 1) Three factors of body images were self appearance evaluation, appearance orientation and fitness orientation. Five factors of clothing attitudes were fashion/clothing interest, clothing exhibition, social approval, psychological dependence on clothing and fashion leadership. And three factors of hair style attitudes were interest in hair style, individuality in hair style and dependency on hair designer. 2) As the result of analyzing the effects of sensation seeking and body image on clothing behavior, fashion/clothing interest was explained by appearance orientation and fitness orientation, and clothing exhibition by sensation seeking and appearance orientation, and social approval by appearance orientation, self appearance evaluation and body cathexis, and fashion leadership by appearance orientation, fitness orientation and self appearance evaluation, and clothing conformity to the self-entertainer by appearance orientation, sensation seeking and fitness orientation, and appearance related delinquency by sensation seeking, appearance orientation, fitness orientation, self appearance evaluation. 3) As the result of analyzing the effects of sensation seeking and body image on hair style attitudes, interest in hair style was explained by the factors such as appearance orientation, sensation seeking, fitness orientation, and body cathexis, and individuality in hair style by appearance orientation, sensation seeking and self appearance evaluation, and dependency on hair designer by body cathexis.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.6
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• pp.1460-1468
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• 1995

The objective of this paper is to evaluate the material properties of SA106 Gr. C carbon steel and its associated weld manufactured for main steam system of Yonggwang 3,4 nuclear generating stations. A total of 43 tensile and 35 fracture toughness tests were performed and the effects of various parameters such as pipe size, crack plane orientation, test temperature, welding on material properties were discussed. Test results show that the effects of crack plane orientation, test temperature, and welding on fracture toughness were significant while the effects of pipe size, specimen orientation and test temperature on tensile properties were negligible. Especially the dependence of J-R curves on the crack plane orientation appears to be the characteristics of carbon steel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.6
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• pp.539-542
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• 2002

The effect of the superconducting film thickness on the surface resistance has been investigated. Superconducting YBCO thin films have been grown on MgO substrates by pulsed laser deposition. The dependence of the orientation of YBCO film on thickness has been investigated by X-ray diffraction technique. X-ray diffraction indicated that the film orientation was changed by increasing the film thickness and by changing the substrate temperature. The microwave properties of the films with mixed orientations of a-axis and c-axis will be reported for the applications of microwave devices.

• Journal of The Korean Astronomical Society
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• v.29 no.spc1
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• pp.53-54
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• 1996

Based on the database of 128 disk galaxies (66 SO, 62 S and Irr) mailnly compiled from Kent and Gunn (1982) and Doi et a1.(1995) which is complete down to m < 15.6 mag within a radius of $3^{\circ}$, the orientation of spin vectors of disk galaxies of the Coma cluster has been analyzed. The results confirm the morphological dependence of the orientation of disk galaxies found from the analsis of the Virgo cluster. Common features of orientation of disk galaxies of both clusters are outlined.