• Journal of Magnetics
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• v.9 no.4
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• pp.116-120
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• 2004

Hexagonal barium-ferrite ($BaFe_{12}O_{19}$, magnetoplumbite structure; BaM) film with perpendicularly c-axis orientation was successfully deposited on (100) silicon substrates with an MgO (111) underlayer by rf diode sputtering and in-situ heating at $920^{\circ}C$. The magnetic and structural properties of 0.27 ${\mu}m$ thick BaM films on MgO (111) underlayers were compared to films of the same thickness deposited onto single-crystal MgO (111) and c-plane ($000{\ell}$) sapphire ($Al_2O_3$) substrates by vibrating sample magnetometry (VSM), x-ray diffractometer (XRD), and atomic force microscopy (AFM). The thickness dependence of MgO (111) underlayers on silicon wafer was found to have a large effect on both magnetic and structural properties of the BaM film. The thickness of 15 nm MgO (111) underlayers produced BaM films with almost identical magnetic and structural properties as the single-crystal substrates; this can be explained by the lower surface roughness for thinner underlayer thicknesses. The magnetization saturation ($M_s$) and the ratio $H_{cII}/H_{c{\bot}}$ for the BaM film with a 15 nm MgO (111) underlayer is 217 emu/cc and 0.24, respectively. This is similar to the results for the BaM films deposited on the single-crystal MgO (111) and sapphire substrates of 197 emu/cc and 0.10, 200 emu/cc and 0.12, respectively. Therefore, the proposed MgO (111) underlayer can be used in many applications to promote c-axis orientation without the cost of expensive substrates.

• Journal of the Korean Society of Safety
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• v.28 no.1
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• pp.12-17
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• 2013

Considering the wind power system and the rotor blades which are composed of much technology, the wind power blade would be the most dangerous part because it revolves at high speed and weighs about dozens of tons, if the accident happens. Therefore, the light weight composite materials have been replacing as substitutional materials. The object of this study is to examine the delamination and damage for CFRP/GFRP hybrid composite that is used for strength improvement of a wind power blade. The influence of the initial crack length and fiber orientation for the interlaminar delamination was exposed for the blade safety. Plain woven CFRP instead of GFRP was inserted into the layer of the box spar for improving the strength and blade life. DCB(Double Cantilever Beam) specimen was used for evaluating fracture toughness and damage evaluation of interlaminar delamination. The material used in the experiment is a commercial material known as CF 3327 EPC in plain woven carbon prepreg(Hankuk Carbon Co.) and UD glass fiber prepreg(Hyundai Fiber Co.). From the results, crack growth rate is not so different according to the variation of the initial crack length. Mode I interlamainar fracture toughness of fiber direction $0^{\circ}$ is higher than that of $45^{\circ}$. Interlaminar fracture has an effect on fiber direction and K decreased with lower value according to increasing initial crack length. Also energy release rate fracture toughness was evaluated because CFRP/GFRP hybrid composite with a different thickness is under the mixed mode loading condition. The interlaminar fracture was almost governed by mode I fracture even though the mixed mode.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.231-241
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• 2021

The consulting industry is also growing as the use of management consulting increases as the importance of management strategies for the survival of companies due to rapid environmental changes is highlighted. As a result, competition among consulting firms is intensifying, and securing competitiveness is essential. This study tried to confirm the method of securing competitiveness of consulting firms from the perspective of organizational competitiveness through organizational effectiveness. As the consulting service is a knowledge service field, an empirical analysis was conducted for consultants who performed it because professional human resources were a core technology. Exploratory factors, reliability analysis, and regression analysis were performed using SPSS 22.0. As a result of a study on the effect of consultants' organizational effectiveness on customer orientation, it was found that the consultant's organizational commitment and organizational performance had a significant effect. It was possible to confirm the importance of intrinsic motivation to secure the competitiveness of consulting firms in the changing environment. This presented practical implications for organizational management regarding the continuous growth of consulting firms.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.1-9
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• 2021

The purpose of this study is to present the necessary success strategies for the social economy ecosystem and social enterprise stakeholders by empirically examining the structural relationship of factors that affect the sustainable dual performance of social enterprises. Through previous studies, hypotheses and research models were established for the performance factors of social enterprises, and hypothesis testing was performed using PLS-Structural Equation Modeling on 92 sample data collected from the survey. As a result of the analysis, it was found that the social mission, customer orientation, and social network set as performance factors all had a significant positive (+) effect on social performance. In addition, social performance had a significant (+) effect on economic performance by mediating customer orientation and social network excluding social mission, and it was found that the business model strengthened this relationship. In addition to the theoretical significance of demonstrating the structural influence of social enterprise performance factors through this study, practical implications can be found in that it suggests factors that social entrepreneurs should focus on for growth and performance creation.

• Korean Journal of Community Nutrition
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• v.26 no.3
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• pp.155-166
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• 2021

Objectives: Driven by a growth of single-person households and individualized lifestyles, solo dining in restaurants is an increasingly recognizable trend. However, a research gap exists in the comparison of solo and group diners' menu-decision making processes. Based on the self-control dilemma and the temporal construal theory as a theoretical framework, this study compared the ordering intentions of solo vs. group diners with healthy vs. indulgent (less healthy) entrées. The mediating role of consumption orientation and the moderating role of amount of menu nutrition information were further explored to understand the mechanism and a boundary condition. Methods: A scenario-based online survey was developed using a 2 (dining social context: solo vs. with others) × 3 (amount of menu nutrition information: no nutrition information vs. calories vs. calories/fat/sodium), between-subjects, experimental design. Consumers' level of nutrition involvement was controlled. A nationwide survey data (n = 224) were collected from a crowdsourcing platform in the U.S. Data were analyzed using multivariate analysis of covariance, independent t-test, univariate analysis of covariance, and moderated mediation analyses. Results: Findings reveal that solo (vs. group) diners have less (vs. more) intentions to order indulgent menu items due to a more utilitarian (vs. more hedonic) consumption orientation in restaurant dining. Findings also show that solo (vs. group) diners have more (vs. less) intentions to order healthy menu items when the restaurant menu presented nutrition information including calories, fat, and sodium. Conclusions: The findings contribute to the literature of foodservice management, healthy eating, and consumer behavior by revealing a mechanism and an external stimuli of solo vs. group diners' healthy menu-decision making process in restaurants. Furthermore, the findings provide restauranteurs and health professionals with insights into the positive and negative impacts of menu nutrition labelling on consumers' menu-decisions.

• Korean Journal of School Psychology
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• v.18 no.2
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• pp.153-174
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• 2021

The purpose of this study is to verify antecedent variables that positively influence behavioural engagement during school engagement, which is critical to adolescent socialization. The antecedent variable was categorized into the personal characteristics of adolescents who are the main agents of socialization and peer support and teacher support, which can be called social support at school sites. Individual characteristics include strength recognition, strength utilization, and learning goal orientation, and, peer supports include the supports for personality strength and academy, and, teacher supports include the supports for personality strength and perspective change. For this study, a survey was conducted on 539 high school students nationwide, collected data, 33 of them were removed, and 506 data were analyzed. Analysis shows that only learning goal orientation set as a sub-factor of individual characteristics has a static significant effect on behavioral engagement. Finally, based on the findings, we discuss the implications, limitations, and future research tasks of the study.

• Journal of Korea Trade
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• v.26 no.4
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• pp.39-62
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• 2022

Purpose - Along with the growing awareness of environmental sustainability, international green entrepreneurship is expected to realize international sustainable development (ISD) by introducing ecological innovation results, using fewer resources consumption, and reducing negative environmental impacts. Building upon contingency theory and social network theory, this paper attempts to explore the role of home country-based networks (technology ties and business ties) as contingent factors that might impact the effectiveness of entrepreneurial orientation (EO) in promoting ISD among green ventures. Design/methodology - Original data were collected from 127 green ventures in China based on the random sampling technique. These green ventures mainly focus on the lower use of energy or materials, lower CO2 emissions, and higher ecological benefits located in the Fujian province, which highlights green economic growth and economic cooperation with international markets. Moderated hierarchical linear regression analysis was conducted to test our hypotheses concerning the main relationship between EO (innovativeness, proactiveness, and risk-taking) and ISD as well as the moderating effects of home country-based networks (technology ties and business ties) on the main relationship. Findings - Empirical results indicate that: first, both innovativeness and proactiveness positively affect ISD; second, both technology ties and business ties at home might significantly strengthen the positive relationship between innovativeness (or proactiveness) and ISD. However, this study did not find significant moderating effects of technology ties or business ties at home on the relationship between risk-taking and ISD. Originality/value - Since previous literature often gives more focus on the host country context of social networks, this study shifts to a home country-based network context. Therefore, our research might enrich the international green entrepreneurship literature by empirically investigating the contingent value of home country-based networks in the relationship between EO and ISD in the context of an emerging economy such as China.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.8
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• pp.818-823
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• 2012

In order to predict necking behaviour of aluminium sheets, a crystal plasticity model is introduced in the finite element analysis of tensile test. Due to the computational limits of time and memory, only a small part of tensile specimen is subjected to the analysis. Grains having different orientations are subjected to numerical tensile tests and each grain is discretized by many elements. In order to predict the sudden drop of load carrying capacity after necking, a well-known Cockcroft-Latham damage model is introduced. The mismatch of grain orientation causes stress concentration at several points and damage is evolved at these points. This phenomenon is similar to void nucleation. In the same way, void growth and void coalescence behaviours are well predicted in the analysis. For the comparison of prediction capability of necking, same model is subjected to finite element analysis using uniform material properties of polycrystal with and without damage. As a result, it is shown that the crystal plasticity model can be used in prediction of necking and fracture behavior of materials accurately.

• Journal of the Korean Ceramic Society
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• v.32 no.4
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• pp.419-428
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• 1995

Polycrystalline silicon carbide (SiC) thick films were depostied by low pressure chemical vapor deposition (LPCVD) using CH3SiCl3 (MTS) and H2 gaseous mixture onto isotropic graphite substrate. Effects of deposition variables on the SiC film were investigated. Deposition rate had been found to be surface-reaction controlled below reactor temperature of 120$0^{\circ}C$ and mass-transport controlled over 125$0^{\circ}C$. Apparent activation energy value decreased below 120$0^{\circ}C$ and deposition rate decreased above 125$0^{\circ}C$ by depletion effect of the reactant gas in the direction of flow in a horizontal hot wall reactor. Microstructure of the as-deposited SiC films was strongly influenced by deposition temperature and position. Microstructural change occurred greater in the mass transport controlled region than surface reaction controlled region. The as-deposited SiC layers in this experiment showed stoichiometric composition and there were no polytype except for $\beta$-SiC. The preferred orientation plane of the polycrystalline SiC layers was (220) plane at a high reactant gas concentration in the mass transfer controlled region. As depletion effect of reactant concentration was increased, SiC films preferentially grow as (111) plane.

• Transactions of Materials Processing
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• v.29 no.1
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• pp.44-48
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• 2020

Aluminum nitride (AlN), as a substrate material in electronic packaging, has attracted considerable attention over the last few decades because of its excellent properties, which include high thermal conductivity, a coefficient of thermal expansion that matches well with that of silicon, and a moderately low dielectric constant. AlN films with c-axis orientation and thermal conductivity characteristics were deposited by using Pulsed Laser Deposition (PLD). The epitaxial AlN films were grown on sapphire (c-Al₂O₃) single crystals by PLD with AlN target and Y₂O₃ doped AlN target. A comparison of different targets associated with AlN films deposited by PLD was presented with particular emphasis on thermal conductivity properties. The quality of AlN films was found to strongly depend on the growth temperature that was exerted during deposition. AlN thin films deposited using Y₂O₃-AlN targets doped with sintering additives showed relatively higher thermal conductivity than while using pure AlN targets. AlN thin films deposited at 600℃ were confirmed to have highly c-axis orientation and thermal conductivity of 39.413 W/mK.