• Journal of the Korean Applied Science and Technology
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• v.6 no.2
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• pp.67-74
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• 1989

The Kinetics of the Hydrolysis of benzalacetophenone derivatives has been investigated by ultraviolet spectrophotometry in 5% dioxane - $H_2O$ at $50^{\circ}C$. A rate equation which can be applied over wide pH range was obtained. The substituent effect on the hydrolysis of benzalacetophenone derivatives were facilitated by electron attracting groups. Based on the rate equation, substituent effect, general base effect, activation parameters and final product, the hydrolysis of benzalacetophenone derivatives seems to be initiated by the netural molecule of $H_2O$ which does not dissociate at below pH 9.0 but proceeded by the hydroxide ion at above pH 11.0. In the range of pH $9.0{\sim}11.0$ these two reactions occur competitively.

• The Journal of the Korea Contents Association
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• v.9 no.2
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• pp.462-470
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• 2009

As the learning space has expanded, the distance education has become a recent scholarship in teaching-learning method, and also a great type of media, technologies and strategies to support distance education are attracting a fair amount of attention. However in order to manage a distance education system, it is necessary to be endowed user with technical ability and operational expenses. On the other hand, although a web-based system that makes simple may cut cost, it is difficult to analyze learner's behaviors. Therefore, in this paper, we developed a interactive distance system based on individualized questioning, which relies upon learner's knowledge state and applies a efficient individualized learning method. Additionally, this study is instrument to reduce users' technical ability and operational expenses.

• Journal of Distribution Science
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• v.18 no.6
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• pp.77-82
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• 2020

Purpose: In the period of international integration, how is the implementation of intellectual property regulation in developing countries? Do intellectual property rights help attract more Foreign direct investment (FDI)? This study aims to show the effect of intellectual property rights, reflect in the number of patent registered (Patent distribution into two components: Patent_residents and Patent_non-residents) on FDI attraction in Vietnam. Research design, data and methodology: Using Autoregressive distributed lag (ARDL) model for the data collected from 1990 to 2018 with EViews version 9 software. Conclusions: The results indicate that the number of patent protection has a positive effect on FDI in both short term and long term. In particular, only patent registration of foreign individuals and organizations has a significant positive effect on attracting FDI, while that of Vietnamese patents is not statistically significant. From the results of this study, we provide some recommendations to help attract FDI based on raising awareness of intellectual property rights: Increase international cooperation for innovation to learn and encourage patent; Improve the capac ity of inventing as well as the ability to register patents of Vietnamese people; Government agencies are tasked to support a nd review registration procedures; Encouraging patent registration based on the patent.

• Journal of Distribution Science
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• v.18 no.6
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• pp.93-101
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• 2020

Purpose: While crowdfunding functions as a purchasing behavior, it is different from other purchasing behavior. It derives from non-existed idea and leads to production and purchase through continuous idea development with participants and participants' support is a proxy for future sales. This study researches on consumption value, customer's trust and consumer's innovativeness to reveal which constructs of consumption value and customer's trust should be considered. Research design, data, and methodology: Crowdfunding participation intentions were examined using consumer's consumption value and trust of platforms as independent variables, and consumer innovation as a control variable. A total of 175 surveys were used for analysis. The hypothesis was tested using hierarchical regression analysis. Results: The results showed economic, epistemic value and ability, benevolence consumer trust to have a significant effect in crowdfunding participation intentions. The moderating effect of innovation was shown to be significant in only economic value and benevolence. Conclusions: The economic and hedonic value of consumers should be emphasized, as well as the evaluation level of the project itself. Moreover, technology or system safety, competency, and product specific information, as well as user benefits for their ideas are core elements in attracting new participants.

• Journal of Distribution Science
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• v.18 no.9
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• pp.13-18
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• 2020

Purpose: Research and development of human capital in countries bring sustainable development to the nations. Especially for developing countries, the attraction of foreign direct investment not only brings economic growth to the country but also contributes to improving human capital. This study aims to assess the impact of foreign direct investment on human capital in ASEAN countries. Research design, data and methodology: With data collected from ASEAN countries from 1990 to 2019, panel data analysis is performed with revised model types (the Pooled OLS, Fixed effect model, Random effect model and regression with Driscoll-Kraay standard errors). Result: The results of the regression analysis show that FDI has a positive impact on human capital. At the same time, the study also found that public investment in education also positively affects human capital; the life expectancy factor does not affect human capital. Conclusions: With this research result, the authors also proposed a number of solutions to improve human capital by attracting FDI and improving the efficiency of investment for the education of ASEAN countries. Besides, public expenditure on education also plays an important role in raising human capital. Therefore, investment in education should be promoted further in the future.

• Knowledge Management Research
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• v.16 no.2
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• pp.173-192
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• 2015

Domestic paid broadcasting market is largely classified into cable TV, satellite broadcasting and IPTV. Latest starter IPTV began its commercial service in 2009 and reached 10 million subscribers in August 2014 after 6 years of service. It has been growing rapidly by increasing more than 500 thousand subscribers every quarter and has taken its place firmly as one of core domestic paid broadcasting platforms, second only to cable TV. Even with this quantitative growth, 3 major IPTV companies are still running deficit, attracting attention to issue of the vitalization of IPTV business based on qualitative growth. This study draws out revitalizing and hindering factors of Korean IPTV industry through a case study on 'A' corporation which is leading domestic IPTV market and exploratory study based on interviews with experts and, by developing influencing factors into Causal Loop Diagram through system dynamics research methodology, draws out core issues in vitalization of domestic IPTV industry and suggests alternatives. Therefore, it is expected that this study will provide more diverse practical implications than preceding studies which drew out one-dimensional issues and alternatives and help vitalize Korean IPTV industry by minimizing negative effects and maximizing positive ones.

• Journal of Information Technology Services
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• v.8 no.2
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• pp.229-245
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• 2009

The Korean mobile telecommunication service market is faced with a tremendous competitive period, in which the market is entering into the maturity stage with launching of the 3rd generation service and with introduction of mobile number portability. In general, it is more important to sustain the old customers than to attracting new customers, as the life cycle of an industry is entering the maturity stage in which the growth rate of new customers is decreasing gradually or becoming stagnant. Thus, mobile telecommunication business has to seek a way to maintain the existing customers instead of promoting new customers. So this study investigates whether the service quality of mobile telecommunication could have effects on the switching barrier of the industry. In order to test the hypothesis on the effects of service quality of mobile telecommunication in Korea on switching barrier, this study collected the questionnaire response data of students including middle and high school students and undergraduates, who are regarded as the major customers in that mobile telecommunication industry.

• Journal of Information Technology Services
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• v.12 no.3
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• pp.55-71
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• 2013

Mobile communication industry is attracting a lot of attention all over the world and is expected to continue developing endlessly with the current rapid development of IT industry. Nowadays, mobile communication companies of vietnam are competing about service quality in order to retain existing customers and improve customer satisfaction and customer loyalty. This study attempts to research about the effect of mobile communication service quality on customer satisfaction and affecting relationship between customers satisfaction and customer loyalty. In this research empirically examine how mobile communication service quality influence customer loyalty in Vietnam. To do this, after considering characteristics of mobile communication service quality, quality measurement instrument was designed including call quality, call charge, cellphone, added service quality, corporate image, employee's attitude, and behavior. The study finds that all factors of call quality, added servces quality, corporate image, employee's attitude and behavior have positive effect on customer satisfaction except call charge and customers satisfaction also effects customers loyalty positively. From these results, Vietnam domestic mobile communication companies and foreign companies can grasp the general information about Vietnam mobile communication industry, and then, establish customers satisfaction strategies more effectively.

• Journal of Power Electronics
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• v.18 no.2
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• pp.432-444
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• 2018

This paper presents a capacitor voltage balancing topology using a three-level boost converter (TLBC) for a neutral point clamped (NPC) three-level inverter fed surface permanent magnet synchronous motor drive (SPMSM). It enhanced the performance of the drive in terms of its voltage THD and torque pulsation. The main attracting feature of the proposed control is the boosting of the input voltage and at the same time the balancing of the capacitor voltages. This control also reduces the computational complexity. For the purpose of close loop vector control, a software based cost effective resolver to digital converter RDC-less estimation is implemented to calculate the speed and position. The proposed drive is simulated in the MATLAB/SIMULINK environment and an experimental investigation using dSPACE DS1104 validates the proposed drive system at different operating condition.

• Transactions of Materials Processing
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• v.27 no.5
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• pp.314-322
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• 2018

AlSi12 is a heat-resistant aluminum alloy that is lightweight, corrosion-resistant, machinable and attracting attention as a functional material in aerospace and automotive industries. For that reason, AlSi12 powder has been used for high performance parts through 3D printing technology. The purpose of this study is to observe deposition characteristics of AlSi12 powder in a direct energy deposition (DED) process (one of the metal 3D printing technologies). In this study, deposition characteristics were investigated according to various process parameters such as laser power, powder feed rate, scan speed, and slicing layer thickness. In the single track deposition experiment, an irregular bead shape and balling or humping of molten metal were formed below a laser power of 1,000 W, and the good-shaped bead was obtained at 1.0 g/min powder feed rate. Similar results were observed in multi-layer deposition. Observation of deposited height after multi-layer deposition revealed that over-deposition occurred at all conditions. To prevent over-deposition, slicing layer thickness was experimentally determined at given conditions. From these results, this study presented practical conditions for good surface quality and accurate geometry of deposits.