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Yeoju, South Korea

Lee K.Y.,Eulji University | Kim A.,Eulji University | Jeon Y.E.,Eulji University | Kim J.J.,Konkuk University | And 5 more authors.
International Journal of Security and Networks | Year: 2015

eXtensible Access Control Markup Language (XACML) standardised by OCG was widely used in the area of information security. And recently geospatial XACML was standardised. But now, types of information are diversified. Especially, importance of information about time and space is continually increased. We use information to know where or when we do something. For instance, we usually check time or find the way with it. Therefore, Geospatial eXtensible Access Control Markup Language (GeoXACML) is not enough to cover it. In this paper, we propose that spatio-temporal XACML which can accept not only geospatial information but also temporal information. Spatio-temporal XACML is based on and expands standardised GeoXACML in OCG. Its scenario consists of access control between positions of polices. Copyright © 2015 Inderscience Enterprises Ltd. Source

Na H.-Y.,Dankook University | Cho S.-H.,Korea Rural Community Corporation | Jun S.-K.,Yeoju Institute of Technology | Kim Z.-C.,Samsung | Cho W.,Dankook University
Proceedings of the International Offshore and Polar Engineering Conference | Year: 2011

Recently with the development of Abu Dhabi, the United Arab Emirates, the coastal development on the Persian Gulf has been increased. To ensure the stability and serviceability of the coastal structures, the resistance against the horizontal and uplift forces should be considered in the design process of the foundation supporting those structures. Unlike the resistance against compression and lateral forces, however, the pullout resistance of piles has not yet been fully investigated. Furthermore, belled-shape piles are known to be very effective against pullout forces, but research on pullout behavior of belled piles has been limited. Therefore, in this study, the pullout load tests of belled tension piles in four sites in Abu Dahbi were performed, then the bearing capacity, characteristics on load-displacement of piles and load distribution considering skin friction were investigated. In addition, the limit pullout bearing capacity calculated by the three-dimensional finite element analysis and theoretical methods were compared. Copyright © 2011 by the International Society of Offshore and Polar Engineers (ISOPE). Source

Jung Y.-H.,Chungwoon University | An J.-H.,University of Suwon | Do J.-S.,Yeoju Institute of Technology
International Journal of Applied Engineering Research | Year: 2015

In this study, I have performed a quantitative performance evaluation of the electrical power generation with a-Si thin-film PV module as influenced by self-shading buildings (the length of protrusion from walls) and shadow angle, with a view to applying a-SI thin-film PV windows system in collective housing. The study has found out that when the protruded length increases by 50mm from 0mm to 250mm, power generation efficiency decreases to the range between 97.1% and 88.1%, as compared to power output for the module (with a protruded length of 0mm), which is designed not to throw shadow on the module surface. Also, in case shadow is created so that the angle created by the arrangement of PV cells and the shadow is flat, generation efficiency decreased at a steady rate of about 16% as compared to the power output from the module (with a shadow ratio of 0%), which is designed to obviate shadow as the shadow ratio increases by 10% between 0% and 30%. On the other hand, in case a shadow creates a right angle with the arranged PL cells, generation performance is greatly lowered with generation efficiency diminishing from 88.6% to 12.7% when compared to the power output from the module (with ashadow ratio of 0%), which is designed to obviate shadow as the shadow ratio increases between 0% and 30%. © Research India Publications Source

Choi D.-S.,Chungwoon University | An J.-H.,University of Suwon | Do J.-S.,Yeoju Institute of Technology | Lee M.-E.,University of Suwon | Jeon H.-C.,University of Suwon
International Journal of Applied Engineering Research | Year: 2014

This study has implemented an optimized design of a photovoltaic module that can be integrated and applied in the window system for apartment housing in Korea through a simulation analysis and a mock-up test on an a-Si PV module. As a result, designing the lower 50% of window system with an a-Si PV module appeared to be most efficient considering the residential performance (lighting performance) and the power generation efficiency. In this case, it has been analyzed as being able to take charge of 7.3% of the power consumptions per household of apartment housing (based on the floor area of 84m2). © Research India Publications. Source

Kim H.J.,Yeoju Institute of Technology | Cho M.-T.,Korea University | Kim K.-S.,Aaia Cement Co
Lecture Notes in Electrical Engineering | Year: 2016

In this paper, a boost chopper using PV (Photovoltaics) system and PWM (Pulse Width Modulation) voltage type power converter were constructed to provide a pleasant environment to the patients in the hospital wards by controlling temperature, humidity and air-conditioning and heating. For the stable modulation of solar cell, synchronizing signal and control signal were processed using one chip microprocessor. In this thesis, in addition, grid voltage was detected and this grid voltage and inverter output were operated at the same phase for the phase locking with PWM voltage source inverter so that surplus power could be linked to grid. This characteristic were applied on the temperature and humidity sensors in the general buildings and buildings having specific purposes such as hospitals. The good dynamic characteristic of inverter could be obtained by these applications. Also, PWM voltage inverter maintains a high power factor and low-frequency harmonic output so that power can be supplied in the load as well as system. © Springer Science+Business Media Singapore 2016. Source

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