• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.3
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• pp.358-366
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• 2014

This paper proposes a quasi Z-source AC-AC converter with the low DC voltage distribution capability operating as a power electronic transformer. The proposed system has configuration that the input terminals of two quasi Z-source AC-AC converters are connected in parallel, also their output terminal are connected in series. Simple control method of duty ratio was proposed for the in phase buck-boost AC voltage mode and the DC output voltage control. DSP based experiment and PSIM simulation were performed. As a result, the PSIM simulation results were same with the measured results. By controlling the duty ratio under the condition of 100 [${\Omega}$] load, quasi Z-source AC-AC converter could buck and boost the AC output voltage in phase with the AC input voltage, and the same time, the constant DC voltage could be output without affecting the AC output characteristics. And, the DC output voltage 48[V] was constantly controlled in dynamic state in case while the load is suddenly changed ($50[\Omega]{\rightarrow}100[\Omega]$). From the above result, we could know that the quasi Z-source AC-AC converter can act as a power electronic transformer with a low DC voltage distribution capability.

• International Journal of Quality Innovation
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• v.9 no.1
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• pp.41-54
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• 2008

The process capability indices have been widely used to measure process capability and performance. In this paper, we proposed a new process capability index which is based on an actual dollar loss by defects. The new index is similar to the Taguchi's loss function and fully incorporates the distribution of quality attribute in a process. The strength of the index is to apply itself to non-normal or asymmetric distributions. Numerical examples were presented to show superiority of the new index against $C_p$, $C_{pk}$, and $C_{pm}$ which are the most widely used process capability indices.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.21 no.45
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• pp.347-356
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• 1998

For assessing the capability of a process, the quantification of process location and variation is central to understanding the quality of units produced from the manufacturing process. Conventional process capability indices is insufficient to drive out the information for process condition, furthermore it is very difficult to evaluate the process capability accurately when the target value is not consistent with the center of specification, and/or the shape of distribution is changed, but the process incapability indices is enable to provide more detailed information to evaluate the process capability by dividing information about the process mean and variance. In this paper, we have a brief review and comparison about these indices, provide an understanding of the relationships between the process capability indices and the incapability indices. And we explore the strengths and weakness of these indices as they apply to normally distributed process, and to examine the effect that non-normality has on these indices.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.360-362
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• 2000

This paper presents a probabilistic method for describing the transfer capability of one area in an interconnected power system. The approach is based on Monte Carlo simulation scheme. The result of this method is the probability distribution of transfer capability. The distribution yield a general framework for probabilistic analysis of STC. IEEE RTS-24 power system is utilized to evaluate the proposed method.

• Proceedings of the KIEE Conference
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• 1998.11c
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• pp.758-760
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• 1998

This paper provides the results of performance investigation of gas insulated switches(G/S) for distribution power system. In order to investigate anti-contamination capability of G/S we carried out electrical tests and material analysis on the body of G/S and it's accessories. Through this experiment we found out the lead cable of G/S had not anti-contamination capability and G/S had insufficient interval between each phase. In order to improve the performance of G/S for heavy contamination area it is indispensable to replace the lead cable to the new cable which has anti-contamination ability.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.1
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• pp.36-42
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• 2007

The latest cars give much importance in the role of HVAC system that controls the environment of the area for passengers more than just basic capability In this study, we drew the automobile interior as three dimension and arranged a method of numerical analysis on HVAC environment in the automobile interior displaying air current distribution and temperature distribution through simulation of the automobile interior on the ventilation volume and outlet area, The aim of this study is to develop the estimated method for HVAC environment in the automobile interior. Results of numerical analysis, to cool automobile interior needs more considerations if thinking cheerful surroundings of automobile interior air but the more magnitude of outlet is small, the more cooling capability is excellent and realistic countermeasures about a realistic geometry and boundary condition.

• Convergence Security Journal
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• v.7 no.2
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• pp.49-55
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• 2007

Software failure time presented in the literature exhibit either constant, monotonic increasing or monotonic decreasing. For data analysis of software reliability model, data scale tools of trend analysis are developed. The methods of trend analysis are arithmetic mean test and Laplace trend test. Trend analysis only offer information of outline content. From the subdivision of this analysis, new attemp needs the side of the quality control. In this paper, we discuss process capability analysis using process capability indexs. Because of software failure interval time is pattern of nonnegative value, instead of capability analysis of suppose to normal distribution, capability analysis of process distribution using to Box-Cox transformation is attermpted. The used software failure time data for capability analysis of process is SS3, the result of analysis listed on this chapter 4 and 5. The practical use is presented.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.495-508
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• 2020

Economic integration is an indispensable trend in all countries. However, besides the advantages that economic integration brings, there are also disadvantages, such as competition between businesses among states in export activities. Vietnam is a developing country with many advantages, especially, the seafood exporting industry. However, with competitive pressure as well as strategic constraints, Vietnamese seafood exporters still face many difficulties. Therefore, the case study of the Kien Giang province of Vietnam is used to analyze the factors affecting the competitiveness of seafood exporting enterprises. The study applied quantitative research methods with a survey of 350 seafood exporting enterprises in Kien Giang province to achieve the research objectives. The research results identified eleven key factors affecting the competitiveness of seafood exporting enterprises, including (1) vision and strategy of leader; (2) human resources management capability; (3) organization capability; (4) customer-responsive marketing capability; (5) relationship management capability; (6) technical capability; (7) competitors reaction capability; (8) business environment adoption capability; (9) financial capability; (10) products and services innovation capability; and (11) branding management. The research results provided the basis to propose some managerial implications to improve the competitiveness of exporting enterprises in the context of the global economic integration.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.6
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• pp.465-473
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• 2020

The objective of this research is to study the confirmative components of strategic intuition capability and the study of causal influence between strategic intuition capability and firm performance of SMEs in Thailand. The consistency method, structural equation models and empirical data were used to test the influential factors on firm performance. Models were then proposed for the development of the strategic intuition capability of entrepreneurs in Thailand. The research sample consisted of 342 SME provincial champion entrepreneurs listed with Thailand's Office of Small and Medium Enterprises. The research results reveal that the model of strategic intuition capability responded well to the empirical data. Additionally, a relationship was identified between firm performance and the causal influence of the strategic intuition capability of entrepreneurs. In accordance with the empirical data, the strategic intuition capability of entrepreneurs had a significant causal influence on firm performance (Chi-square = 35.71, df = 25, P-value = 0.07615, GFI = 0.98, AGFI = 0.96, RMSEA = 0.033, RMR = 0.027). Furthermore, with respect to the development of strategic intuition capability, the development of genuine wisdom based on systematic knowledge management achieved via conscious mental concentration may lead to the next stage of strategic intuition.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.44 no.3
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• pp.240-247
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• 2021

As competition among companies has intensified and the life cycle of products has been shortened, strong innovation is needed to meet consumers' needs. In addition, it is necessary to shorten the life cycle of the product and reduce the time required for technology development for the competitive advantage of the product. In particular, venture companies where new technologies and ideas are important require more innovative capabilities than others companies. Therefore, this study analyzed the impact of technology innovation capabilities (product development process capability, human resource capability and financial capability) on sales by technology development for small and medium venture companies and analyzed moderating effect of technology development period on the relationship between technology innovation capabilities and sales by technology development. The data of 'Small and Medium Business Technology Statistics' collected by the government every year were used for analysis. Technology-intensive ventures were extracted from this data. In addition, the moderating effect was analyzed through hierarchical regression analysis. This study shows that product planning capability, test capability, and R&D expenditure have a positive impact on sales by technology development. In this study, the product development period showed a positive moderating effect on product development capability and sales performance. On the other hand, the product development period showed a negative moderating effect on R&D expenditure and sales by technology development.