• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.29 no.7
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• pp.87-94
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• 2015

Recently, renewable energy sources are under the spotlight. due to the depletion of fossil fuels and environmental problem for the carbon dioxide. Among them, research on the Photovoltaic System using solar energy systems has been actively conducted. In this paper, we propose boosting the insulated DC/DC converter topologies Applied to soft-switching methods used in photovoltaic PCS. The proposed topology is of a type that combines a series of full-bridge converter and a boost converter, a full bridge converter and applying the insulation and soft switching system, the output voltage boost stage is carried out for the boost control. The proposed circuit validity was verified through the PSIM simulation and 5kW PV PCS Prototype and experiments.

• Proceedings of the KIPE Conference
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• 2008.06a
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• pp.529-531
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• 2008

Generation system using regenerative energy like photovoltaic, fuelcell is increased, PCS technology coming into the spotlight. The efficiency of DC-DC converter as part of the PCS is very important, multi-phase boost converter has more advantage than other topology. Input current of the multi-phase boost converter is divided into two inductor current because of parallel structure of the boost converters, thus it has features of decreasing input current ripple and output voltage ripple. Also multi-phase boost converter with soft switching can decrease switching loss using ZCS and ZVS. In this paper, simulation and experiment are performed to verify operation of the proposed converter, and efficiencies of the conventional and proposed converter are compared.

• The Journal of Sustainable Design and Educational Environment Research
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• v.7 no.2
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• pp.1-11
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• 2008

Recently, it is throwing the spotlight on environment-friendly architecture for preservation of the global environment throughout the world. At this point in time, home products to have Eco-label in architecture materials is increasing constantly and the demand of environment-friendly building and material is rising. The purpose of this study is to propose a way of development through analysis about necessity and concept of environment-friendly architecture and research into institution and standard for certification of environment-friendly building materials. So, it will make exactly progress to this study that is based on analysis and research of periodical publications, theses, reports of journal and data of the advanced country about environment-friendly architecture.

• International Journal of High-Rise Buildings
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• v.1 no.1
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• pp.21-28
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• 2012

Diagrid system has been in the spotlight for its superiority in terms of the resistance to lateral force when applied to skyscrapers. In diagrid system, most of columns can be eliminated because vertical loads (gravity loads) and horizontal loads (lateral loads) are delivered simultaneously thanks to the triangular shape of diagrid. However, lack of studies on connection shape and node connection details makes it hard to employ the system to the buildings. In this study, the structural safety of the node connections in circular steel tube diagrid system which has been considered in the Cyclone Tower in Korea (Seven stories below and fifty-one above the ground) was evaluated using the 4 full-scale specimens. The parameters are the extended length (20 mm, 40 mm & 60 mm), thickness (40 mm & 50 mm).

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.808-811
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• 1997

MMC has excellent mechanical properties in many ways in automotive industrial, and get into the spotlight as a light materials substituted for iron and steel. But the know-how about MMC research lack, MMC is expensive and difficult to apply the sound parts. Especially it is difficult to produce the hollow type parts composed with MMC. Therefore, hollow type parts of metal composites by using thixoforming process which as co-existing solidus-liquidus phase, it is very important to obtain forming condition. In this study, MMC billet producted by electro-magnetic stirring and mechanical stirring process is formed to hollow type parts of thixoforming process and inspected of suitability for application. It is optimized production condition, and applied to experiment. After variable materials were produced for thixoforming process, it were inspected of suitability for application by comparsion with mechanical properties. In this study, used materials were A357, A380 10%vol, and 20%vol SiCp, and the size of particultes were 14$\mu\textrm{m}$ and 5.5$\mu\textrm{m}$.

• International Journal of Quality Innovation
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• v.9 no.1
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• pp.134-152
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• 2008

Almost every country around the world has been focusing on food safety in intense and multifaceted ways. The use of Hazard Analysis Critical Control Points (HACCP) is widely accepted as a food safety management system. This paper investigates the success factors of HACCP practices with reference to the domains of food production, processing and delivery. A literature review of food safety and management articles was conducted. Using the keywords search, the online Emerald Database was used and a total of 102 journal articles were identified between 1994 and 2007. The study examined a list of 20 success factors. Results show that 'food regulations,' 'role of the industry,' 'government policies and interventions,' 'training on food safety and hygiene,' and 'food contamination and/or poisoning' share the spotlight as being the most critical factors for HACCP practices in organisations. Future research could investigate a holistic paradigm that incorporates the success factors and aligns HACCP measures for attaining safety performance goals.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.268-271
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• 2009

In this paper, we analyze social network status and suggest TV SNS Service. According to alexa.com's recent chart, there are three SNS sites (facebook, myspace, twitter) in global top 20 sites. SNS usage has increased dramatically. Recently many SNS are growing up by opening their platform that make it easy to develope new services and functions by third party developers. KT is implementing open platform that is support Widget and SNS service. And Recently Social TV comes into the spotlight. Social TV is combination of social media and TV contents. It is enable to exchange emotion and opinion by communication with other people when watching Video contents. We propose TV SNS Service that provides various services by using advantage of SNS system and Social TV.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.117-120
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• 2009

In this paper, a CR(Cognitive Radio) based on SDR(Software Defined Radio) is the technology combined a method selecting available frequency by recognizing surroundings with a learning algorithm continuously updating basic functions for communication and various environment parameters. Recently, as increasing demands with development of wireless communication service, CR is in the spotlight as technology using frequency resource efficiently. In order to apply CR system to the terminal and implement it, the research field to be preceded can be divided large as a hardware part and a software part. It can be also divided into RF processing and digital signal processing in the hardware part. In this paper, we look over preceding techniques required for applying CR system to the terminal, and research the forms of the terminal when they practically apply to the terminal.

• International Journal of Advanced Culture Technology
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• v.4 no.4
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• pp.70-74
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• 2016

Electronic commerce (E-commerce) using virtual reality (VR) has the advantage of being able to purchase products without restrictions of time and location by overcoming the limitations of existing offline transactions. It is still a rudimentary but fast growing technology, and the use of E-commerce in VR is expanding. The barriers that consumers might face in utilizing E-commerce in VR is the relevance to Information and Communications Technologies (ICT) technology. Fundamentally, it requires Internet access and use through PCs or mobile devices such as smart phones. Because unlike off-line markets, it is difficult to determine the purchase patterns of customers, customer purchasing behavior analysis must be done using computer access records. In order to expand and develop E-commerce in VR in the future, learning ability should be improved through combining with artificial neural network by deep learning that is recently in the spotlight, and the ability to overcome errors need to be improved to enable use in various fields.

• Proceedings of the IEEK Conference
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• 2002.07b
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• pp.838-840
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• 2002

Presently, Analytic Network Process which evaluates man's intention and offers decision-making support is capturing the spotlight. It originates in the ability of Analytic Network Process to treat various decision-making support system. However, no detailed reference is available when dealing with the group case. This paper examines the technique, which can also cope with the group decision-making support system, and describes the validity of the technique. A characteristic feature of the proposed technique is that it can detect a group's intention in a given section, and it decomposes the sectional supermatrix into a small supermatrix and a large one. A general supermatrix treats the convergence value by taking the limiting process method of the power of an evaluation value. On the other hand, when a supermatrix has nonnegative value, it can easily be solved by the eigenvector method. The decomposition of the supermatrix has been considered in this work.