• Journal of Electrical Engineering and Technology
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• v.8 no.6
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• pp.1400-1408
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• 2013

This paper proposes a new grid-tied power converter for battery energy storage, which is composed of a 2-stage DC-DC converter and a PWM inverter. The 2-stage DC-DC converter is composed of an LLC resonant converter connected in cascade with a 2-quadrant hybrid-switching chopper. The LLC resonant converter operates in constant duty ratio, while the 2-quadrant hybrid-switching chopper operates in variable duty ratio for voltage regulation. The operation of proposed system was verified through computer simulations. Based on computer simulations, a hardware prototype was built and tested to confirm the technical feasibility of proposed system. The proposed system could have relatively higher efficiency and smaller size than the existing system.

• Journal of the Korean Society of Industry Convergence
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• v.3 no.2
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• pp.123-130
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• 2000

Fuzzy control is proposed to regulate cutting force in turning operations under varying cutting conditions. The traditional linear controllers based on crisp mathematical model cannot effectively control cutting force becasue of the nonlinear dynamics of turning operations. The proposed fuzzy controller is based on operator experience and expert knowledge. The membership functions for the inputs and the output of the controller are designed. Cutting force is regulated by adjusting feedrate according to the variation of cutting conditions. The performance of the proposed controller is evaluated by experiments. The results of experiments show that the proposed fuzzy controller has a good cutting force regulation over a wide range of cutting conditions.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.4
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• pp.8-13
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• 2008

Since hundreds thousands of pedestrians are killed or injured in car accidents every year, a variety of research efforts have been performed to protect pedestrians in pedestrian-vehicle crashes. The IHRA reports that injuries on the child head, the adult head, and the adult lower leg/knee are the most critical in the crashes. Identifying the current status of international activities on pedestrian protection, this study, in particular, carries out headform impact test using selected domestic vehicles categorized by three groups - Sedan, SUV (Sport Utility Vehicle), and 1 Box (One Box) Vehicle. According to the valuable findings from the test results, this paper proposes a methodology under which the Korean Technical Regulation for protecting pedestrians in pedestrian-vehicle crashes will be developed.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.105-110
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• 2013

After analog broadcast changed to digital, the dynamic range of the broadcast audio became wider. As there are no regulation for digital broadcast audio level, the audio level of digital TV is gradually increasing, and this phenomenon is getting more serious. because of competition between broadcasters and programmes. To solve this problem, ITU-R legislated technical recommendations for digital TV audio level. In this paper, the audio levels of domestic TV channels are measured according to the algorithm of the ITU-R, and analyzed management method is suggested.

• Proceedings of the Korea Contents Association Conference
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• 2003.05a
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• pp.474-479
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• 2003

We discussed the usage of a radio resource, the spectrum allocation and the trends of policy about 5㎓ band in other countries, We studied about the technical regulation on high speed wireless access system and the spectrum allocation of ISM bard in 5㎓ bard for other countries. We also analyzed the efficient use of radio resource, the method of frequency sharing and the calculation of spec01m requirement in noel to progress the high speed wireless access system In addition We proposed the schemes of domestic spectrum allocation for high speed wireless access system at 5㎓ band

• The Journal of Industrial Distribution & Business
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• v.7 no.1
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• pp.19-25
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• 2016

Purpose - The purpose of this paper is to aim to stress the importance of doing business environment in South Korean economy. The theoretical justification is based on neo-institutional theories and new business management including Porter's Model as main justifications of state intervention due to the market failures to promote a competitive environment of doing business. Research design, data and methodology - The methods to be taken is to provide a comparative performance analysis, and offer in terms of doing business and economic freedom sub-index complemented by Korean reforms diagnostics. Results - The main results underlined the key factors explain the success of business environment in South Korea such as: a simplified registration procedures, a target tax incentives, the removal of business barriers, the improvement of legislative and regulatory framework, target reforms, property right and technical norms, good governance and the quality of institution, a role of a well-functioning legal framework, a strong competition framework, and the transparency of regulation, etc. Conclusion - A competitive environment of doing business is based on the target national strategies, appropriate reforms responding to national needs and good governance system.

• Journal of the Korean Society of Safety
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• v.35 no.4
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• pp.1-8
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• 2020

Intensity of accidents associated with dangerous machines and devices are (hereafter items), in general, high compared to other industrial accidents. This study focuses on cause analysis of accidents associated with items that are subject to safety certification. The method is based on automated analysis of abstracts of accidents written in descriptive format. The analysis results indicate that more than 50% of accidents associated with items are caused by technical reasons and nearly 50% of accidents were preventable. More effective prevention of industrial accidents would then be realized by safety certification at the stage of danger generation. Transition from the direct regulation on users to manufacturers is also needed to improve the effectiveness and efficiency of industrial safety system in Korea.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1998.11a
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• pp.221-224
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• 1998

Environmental pollution is continuously increasing with the economic growth and industrial development. With this trend, soil and groundwater pollution problem has been surfaced as important social issues. Recently, Korean government promulgated the Soil Environment Conservation Act. But there are many problems to control sound soil quality management. Anthropogenic source of pollution such as waste landfill, pesticides, fertilizer, underground storage oil tanks is important as well as natural source such as acid rain and forest fire. The regulation should be expanded to include groundwater preservation as well as soil quality, because soil pollution is closely related to groundwater pollution. Therefore, legal regulations must be expanded to these facilities and take into account technical feasibility and finance.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2005.11b
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• pp.73-76
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• 2005

Recently, the demand for the Floating, Production, Storage, and Offloading facility (FPSO) which has some economic and technical advantages, has increased in offshore oil production areas. FPSO vessel dose not have self-propulsion system, but has additional facilities for oil production and positioning system. Main noise sources such as gas turbines, compressors, and pumps, are located on top of the hull (Topside area). In general, the noise regulation for the offshore structure is severer than that of the cargo ship and acceptable noise limit of cabin is specified as 45 dB(A). This paper describes the noise characteristics and the countermeasures for FPSO Topside area through investigation of noise analysis and site measurement results. Proper countermeasures, considering the characteristics of sources and receiver spaces, were applied from the noise prediction and various measurement results. Finally, this ship was successfully delivered with excellent noise properties.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.163-168
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• 2005

In case of rolling stock, SEMS is generally applied in the advanced countries, but is start stage in our country. SEMS is defined the system engineering management system in order to achieve the optimized train performance among the several client requirements aspect of technical engineering management during the design life cycle. And the fire engineering activities in hong kong EMU project are introduced aspect of SEMS in this paper. The fire engineering at rolling stock in view of SEMS controls to apply the satisfied interior material by the fire safety standards (regulation of the commute urban subway safety guideline by the MOCT, BS 6853, NFPA 130, NF F 16-101) and to minimize the fire load in order that passengers egress safe from the fired rolling stock. The rolling stock in the advanced countries is designed to stand for 15-20 minutes in considering the rolling stock to be fired in tunnel. For passenger fire safety, the passenger evacuation provision and progress is set up.