• Journal of the Korean Crystal Growth and Crystal Technology
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• v.19 no.5
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• pp.215-222
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• 2009

Many concepts of external magnetic field applications in crystal growth processes have been developed to control melt convection, impurity content and growing interface shape. Especially, travelling magnetic fields (TMF) are of certain advantages. However, strong shielding effects appear when the TMF coils are placed outside the growth vessel. To achieve a solution of industrial relevance within the framework of the $KRISTMAG^{(R)}$ project inner heater-magnet modules(HMM) for simultaneous generation of temperature and magnetic field have been developed. At the same time, as the temperature is controlled as usual, e.g. by DC, the characteristics of the magnetic field can be adjusted via frequency, phase shift of the alternating current (AC) and by changing the amplitude via the AC/DC ratio. Global modelling and dummy measurements were used to optimize and validate the HMM configuration and process parameters. GaAs and Ge single crystals with improved parameters were grown in HMM-equipped industrial liquid encapsulated Czochralski (LEC) puller and commercial vertical gradient freeze (VGF) furnace, respectively. The vapour pressure controlled Czochralski (VCz) variant without boric oxide encapsulation was used to study the movement of floating particles by the TMF-driven vortices.

• Journal of the Korean Academy of Esthetic Dentistry
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• v.24 no.1
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• pp.68-74
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• 2015

The growing of healthy aged edentulous peoples in these days increases the demands of denture which is excellent in function and aesthetic. The Biofunctional Prosthetic System(BPS) is being introduced as a curriculum in a large number of schools in the United States, Europe and Japan. Each stages of BPS are standardized and systematized, on this account BPS is the system that even less experienced clinicians is able to produce highly satisfactory denture for patients. Additionally, the combination of BPS and suction mechanism of mandibular complete denture would make it possible to produce stabilized mandibular denture during oral function. The purpose of this article is to describe a process of producing fuctionally and aesthetically outstanding denture by using BPS combined with mandibular suction mechanism.

• Journal of Information Technology Applications and Management
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• v.23 no.1
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• pp.1-23
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• 2016

Social commerce (s-commerce) is a subset of e-commerce and uses social media for social interactions. Although s-commerce has been rapidly growing, disputes between some s-commerce firms and their consumers often occur over issues such as poor customer services, incorrect product information, and late refunds. In order for s-commerce to continuously grow, s-commerce firms need to build consumer-trust in their transaction process to minimize their consumers' uncertainty. The purpose of this study is to examine the relationships between the multidimensional trust (ability, integrity, benevolence) and the intention of continuous use of s-commerce. Moreover, this study presents antecedent factors needed for trust-building by applying the characteristics of s-commerce, and verifies the relations between the variables. We test and validate the research model and related hypotheses using structural equation modeling based on a survey done on 428 people who have previous experience with s-commerce. The result shows that trust has positive effect on the intention of continuous use, and verifies the necessity of the antecedent factors (social presence, assurance, informativeness, economic feasibility, and seller reputation) for trust-building. This study provides strategy for the continuous growth of s-commerce, and suggests theoretical implication that explains the relationship between the characteristics of s-commerce and consumers.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.2
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• pp.111-119
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• 2006

In the last decade, the research of the usability of mobile phones has been a newly evolving area with few established methodologies and realistic practices that ensure capturing usability in evaluation. Thus, there exists a growing demand to explore appropriate evaluation methodologies that evaluate the usability of mobile phones quickly as well as comprehensively. This study aims to develop a task-based usability checklist based on heuristic evaluation in views of mobile phone UI practitioners. A hierarchical structure of UI design elements and usability principles related to mobile phones were developed and then utilized to develop the checklist. In order to demonstrate the practical effectiveness of the proposed checklist, comparative experiments were conducted on the usability checklist and usability testing. A majority of usability problems found by usability testing and additional problems were discovered by the proposed checklist. It is expected that the usability checklist proposed in this study could be used quickly and efficiently by usability practitioners to evaluate the mobile phone UI in the middle of the mobile phone development process.

• Preventive Nutrition and Food Science
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• v.22 no.2
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• pp.81-89
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• 2017

Healthy aging has become a major goal of public health. Many studies have provided evidence and theories to explain molecular mechanisms of the aging process. Recent studies suggest that epigenetic mechanisms are responsible for life span and the progression of aging. Epigenetics is a fascinating field of molecular biology, which studies heritable modifications of DNA and histones that regulate gene expression without altering the DNA sequence. DNA methylation is a major epigenetic mark that shows progressive changes during aging. Recent studies have investigated aging-related DNA methylation as a biomarker that predicts cellular age. Interestingly, growing evidence proposes that nutrients play a crucial role in the regulation of epigenetic modifiers. Because various nutrients and their metabolites function as substrates or cofactors for epigenetic modifiers, nutrition can modulate or reverse epigenetic marks in the genome as well as expression patterns. Here, we will review the results on aging-associated epigenetic modifications and the possible mechanisms by which nutrition, including nutrient availability and bioactive compounds, regulate epigenetic changes and affect aging physiology.

• Journal of the Korean Home Economics Association
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• v.48 no.6
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• pp.133-147
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• 2010

This study aimed to identify the dimensions of successful aging, as perceived by elderly Koreans, and to test qualitatively the elders' optimization of selection and compensation strategies in a social activity context. The results were as follows: First, the most important part of life fulfillment and regret was family and work. Second, social activity played a role in self-actualization and physiological needs. Moreover, it contributed to the elders' physical and mental health maintenance. Third, the elderly effectively participated in social activities by optimizing their selection and compensation strategies. Fourth, the elderly realized they are growing old, but considered it as a natural process. In addition, some participants suggested retirement age should be raised, but others were against this idea. Finally, elders thought successful aging means having a sufficient and independent life in old age. Thus, the elderly required good health, economic security, and a positive attitude for aging successfully.

• Journal of Korea Game Society
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• v.9 no.6
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• pp.93-103
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• 2009

The domestic online game market is rapidly growing and changing because of the game service that makes game users agreeable to their characters. However, the game service cannot satisfy with game users' need because it only considers game users' characters. As a result of this, there gives rise to side effects such as a secession from a customer group and a boycott. Furthermore, these have effect on life or death in the game market. Therefore, the purpose of this study examines game users' dissatisfaction and satisfaction about online game how to express. Through this process, this study willing to suggest a strategy for recovering service of the game company.

• Wind and Structures
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• v.25 no.2
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• pp.177-193
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• 2017

The accelerated development of new materials, technologies and construction processes, in parallel with advances in computational algorithms and ever growing computational power, is leading to more daring and innovative architectural and structural designs. The search for non-regular building shapes and slender structures, as alternative to the traditional architectural forms that have been prevailing in the building sector, poses important engineering challenges in the assessment of the strength and mechanical stability of non-conventional structures and systems, namely against highly variable actions as wind and seismic forces. In case of complex structures, laboratory experiments are a widely used methodology for strength assessment and loading characterization. Nevertheless, powerful numerical tools providing reliable results are also available today and able to compete with the experimental approach. In this paper the wind action on a free-form complex thin shell is investigated through 3D-CFD simulation in terms of the pressure coefficients and global forces generated. All the modelling aspects and calibrating process are described. The results obtained showed that the CFD technique is effective in the study of the wind effects on complex-shaped structures.

• Journal of the Korea Institute of Military Science and Technology
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• v.17 no.5
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• pp.654-662
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• 2014

In the development of the weapon systems, utilization of Modeling & Simulation is growing in every aspect of development process. For the higher utilization of M&S, reuse of the M&S resources is needed to reduce the cost of M&S. I propose the M&S architecture framework that can enhance the reusability of the M&S resources in developing surface-to-air weapon systems. This M&S architecture design framework enables interoperability between the system and sub-systems. In this paper, the advantage and the necessity of the M&S architecture design framework will be described by introducing the cases that the M&S architecture framework reused in the combat experiments, the system development tests, the system operational tests and the concept developments in real projects. These cases will show the high reusability and efficiency of the M&S architecture design framework.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.364.2-364.2
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• 2014

Magnesium oxide (MgO) thin films have attracted great scientific and technological interest in recent decades. Because of its distinguished properties such as a wide band gap (7.2 eV), a low dielectric constant (9.8), a low refractive index, an excellent chemical, and thermal stability (melting point=$2900^{\circ}C$), it is widely used as inorganic material in diverse areas such as fire resistant construction materials, optical materials, protective layers in plasma display panels, buffer layers of multilayer electronic/photonic devices, and perovskite ferroelectric thin films. Precursor used in the ALD requires volatility, stability, and low deposition temperature. Precursors using a heteroleptic ligands with different reactivity have advantage of selective reaction of the heteroleptic ligands on substrate during ALD process. In this study, we have synethesized new heteroleptic magnesium precursors ${\beta}$-diketonate and aminoalkoxide which have been widely used for the development of precursor because of the excellent volatility, chelating effects by increasing the coordination number of the metal, and advantages to synthesize a single precursor. A newly-synthesized Mg(II) precursor was adopted for growing MgO thin films using ALD.