• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.749-753
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• 2003

This paper presents an output voltage regulation system using PWM Buck-Boost AC-AC converter for power qualify improvement of custom power. This paper proposes dynamic modeling of the system for control object and in addition, a controller design example. Therefore, system state equation is derived whereby the transfer function could be obtained. The paper shows a regulation controller for tracking the output voltage to the reference under specific operating point. Finally, this paper shows validity and practical applicability of the proposed modelling and system design by experimental results.

• Journal of Applied Reliability
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• v.17 no.4
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• pp.362-369
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• 2017

Purpose: Recently, the government of China has established new safety regulations for towing devices. The new Chinese regulation has more unfavorable conditions than the conditions of other countries. So the various measures have been reviewed to satisfy this regulation. Methods: The regulation conditions were compared through analysis of strain energy, and a method for improving the accuracy of analysis is suggested. In addition, the test method considering the tolerance is presented through tolerance analysis. This paper also explained importance of confirming the quality of products through a case of poor quality of Chinese products such as poor heat treatment. Result: We could know how strong Chinese regulations are stronger than other national laws and investigated which member receives a lot of strain energy. In order to cope with these Chinese regulations, we suggested improvement of analysis accuracy, test method through tolerance analysis, and heat treatment quality. Conclusion: This paper contributed to general counterplan of the strengthened new Chinese regulations for towing device.

• Korean Journal of Exercise Nutrition
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• v.15 no.4
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• pp.153-161
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• 2011

The maintenance of skeletal muscle mass is very important for the prevention of life style-related diseases and the improvement of quality of life. It is well-known that resistance exercise and nutrition (especially amino acids) are the most effective interventions for maintaining skeletal muscle mass. It has been reported that many molecules are involved in the regulation of protein synthesis in response to resistance exercise and nutrition. Understanding the molecular mechanisms regulating muscle protein synthesis is crucial for the development of appropriate interventions. The role of intracellular signaling pathways through the mammalian target of rapamycin (mTOR), a serine/threonine protein kinase in the regulation of muscle protein synthesis, has been extensively investigated for these years. Control of protein synthesis by mTOR is mediated through phosphorylation of downstream targets that modulate translation initiation and elongation step. In contrast, upstream mediators regulating mTOR and protein synthesis in response to resistance exercise and amino acid still needed to be determined. In this brief review, we discuss the current progress of intracellular mechanisms for exercise- and amino acid-induced activation of mTOR pathways and protein synthesis in skeletal muscle.

• Journal of Distribution Science
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• v.15 no.12
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• pp.53-60
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• 2017

Purpose - This paper analyzes the effect of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation, which are the main regulation adopted in "Law on the Improvement of the Mobile Terminal Distribution System" (Mobile Terminal Distribution Act), on the social surplus, the consumer surplus and profits of telecommunications carriers. We focus our analysis on whether the service charge competition is stimulated enough so that it can compensate for the loss of subsidies. Research design, data, and methodology - We use simple economic model to assess the impact of the handset subsidy and the Mobile Number Portability subscriber subsidy regulation. Unlike the former researches on this topic, we depart from using Hotelling model, and instead use the switching cost model, which uses switching cost as a parameter of market powers of telecommunications carriers. We also study the effect of the two different regulations when they are adopted both independently and concurrently. Results - If the market powers of telecommunications carriers are over certain threshold, contrary to the regulatory agency's assertion, the service charge competition would not be stimulated enough to compensate for the deduction in the subsidies, and thus the consumer surplus is compromised. Number Portability subsidy, especially, undermines the rival's market power and thus reduces the service charge. On the other hand, the regulations will also increase the profits of telecommunications carriers. However, social surplus is maximized when both of the regulations are present because the regulations reduces the frequency of switching handsets inefficiently. Conclusions - In enacting the Mobile Terminal Distribution Act, the telecommunications regulatory agency asserted that the regulation on subsidies will stimulate service charge competition, and in the long run, enhance the consumer surplus. However, contrary to the regulatory agency's assertion, subsidy regulation, especially the regulation on Number Portability subsidy, reduces consumer surplus. On the other hand, the Mobile Terminal Distribution Act can also increase the profits of telecommunications carriers because it decreases competition among the telecommunications carriers. However, the Mobile Terminal Distribution Act can increase the social surplus because it reduces inefficient switching of handsets.

• Proceedings of KOSOMES biannual meeting
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• 2017.04a
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• pp.75-75
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• 2017

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.53 no.11
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• pp.610-618
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• 2004

With the development of industry and the improvement of living standards, better quality in power electric service is required more than ever before. Under these circumstances, to deliver reasonable voltage regulation methods in distribution systems need to be developed. So, This paper deals with optimal introduction of the line voltage regulator (SVR : Step Voltage Regulator) in power distribution systems. First, This paper investigates characteristics of SVR and performs economic evaluation of SVR's introduction by using Present Worth Method. This paper, also suggests proper location and optimal voltage regulation algorithm. In order to deliver suitable voltages to as many customers as possible, the optimal sending voltage of SVR should be decided by the effective operation of voltage regulators at the distribution feeders. The simulation results using a model distribution system and real distribution systems show that the proposed methods can be a practical tool for the voltage regulation in distribution systems.

• The Korean Journal of Community Living Science
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• v.18 no.4
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• pp.671-679
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• 2007

This study investigated the relationship between maternal facilitative communication perceived by children and the social adjustment which was measured as pro-social behaviors and aggressive behaviors in children. Special attention was given to the mediating effect of the child's self-regulation on the relationship. The subjects, selected by convenience sampling method, were 193 fourth and fifth grade elementary school students. Data was analyzed through Pearson's correlation, reliability analysis, and multiple regression using the SPSS 12.0. The findings of the study were as follows. First, the mother's facilitative communication perceived by the child was positively associated with the pro-social behavior, while, it was negatively correlated with the aggressive behavior of the child. Second, the mother's facilitative communication had direct effect on the prosocial behavior and the aggressive behavior of the child. Third, the direct impact of facilitative communication on social adjustment was mediated by the self-regulation variable. Based on these findings, this study proposes strategies for the improvement of children's adjustment during late childhood.

• Korean Journal of Environmental Agriculture
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• v.33 no.1
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• pp.63-67
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• 2014

BACKGROUND: The present study is an exploratory research to establish national biosafety regulation systems through a survey on the recognition of safety regulation systems for the living modified organism(LMO). METHODS AND RESULTS: We have conducted a survey on an awareness of LMO safety regulation systems in scientific working groups. The data of 235 respondents were analyzed using various statistical methods. As a result, 72.8% of the respondents were male; 27.2% were female, and 43.4% of them work in the university. A total of 33.2% of the respondents majored in general biology, and their most common job position was the laboratory safety manager. The difference of an awareness on LMO law and regulatory system was not statistically significant by either work places or job positions. CONCLUSION: For the rapid settlement and the efficient implementation of LMO safety management policy, we conclude that it is required to reduce the gap between the recognition and fulfillment of safety management. Furthermore, the mutual exchanges of information among researchers are needed with the settlement of the safety management system and the harmony of policy with improvement of the absurd regulations. The ongoing and specialized training, inspections, and the strengthening of public relations are also required along with the efforts to improve the absurd regulations.

• The Transactions of the Korean Institute of Power Electronics
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• v.23 no.5
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• pp.345-351
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• 2018

A distributed control method is proposed to improve the power sharing performance of bidirectional distributed generators and the voltage regulation performance of a DC bus in a DC microgrid. Voltage sensitivity analysis based on power flow analysis is conducted to analyze the structural characteristics of a DC microgrid. A distributed control method using a voltage sensitivity matrix is proposed on the basis of this analysis. The proposed method uses information received through the communication system and performs the droop gain variation method and voltage shift method without additional PI controllers. This approach achieves improved power sharing and voltage regulation performance without output transient states. The proposed method is implemented through a laboratory-scaled experimental system consisting of two bidirectional distributed generators, namely, a load and a non-dispatchable distributed generator in a four-bus ring-type model. The experimental results show improved power sharing accuracy and voltage regulation performance.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.189-192
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• 2021

The article is devoted to the issue of the content of legal instruments in terms of tourism business, namely the problems of legal regulation of insurance in tourism. The analysis of the state of development of the problem in question shows that the issue of legal regulation of the insurance contract in general and the contract in tourism services, in general, is insufficiently studied. The article is devoted to topical issues of legal regulation of insurance in the field of tourism, the search for effective mechanisms to increase the liability of both underwriters and insurers. Therefore, insurance can be considered as one of the methods of preventing unfortunate consequences during the implementation of tourism activities. The author's vision of the content of the package of measures that can positively influence not only the development of the tourist industry in general but primarily to help identify those legal segments that need improvement in the future has been stated.