• The Transactions of the Korean Institute of Electrical Engineers B
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• v.52 no.10
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• pp.491-500
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• 2003

Most of the loads in industrial power distribution systems are balanced and connected to three wires power systems. However, in the user power distribution systems, most of the loads are single & three phase and unbalanced, generating a large amount of non-characteristic harmonics. With the advent of power electronics and proliferation of non-linear loads in industrial power applications, power harmonics and their effects on power quality are a topic of concern. Harmonics by the unbalance voltage and non-linear loads, cause the increase of machine loss and heating. In order to allow current harmonic compensation, a filter must be installed. This paper describes the performance of passive filter under the voltage unbalance and non-linear load.

• Journal of Korean Society for Quality Management
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• v.29 no.3
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• pp.151-165
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• 2001

The purpose of this study is to develop systematic methods for evaluating the suitability of a seat and build an empirical model for predicting the suitability of a seat. The following research schemes were pursued to achieve the objectives - Development of suitable chair dimensions - Analysis scheme for decomposing the human-product interface system - Development of model for evaluating suitability. As a result, we uncovered six dominant suitability dimensions for the design of a comfortable seat that is related to the physical dimension of a body, Here, six suitability dimensions were identified as the dimensions that represent the human sensitivity and psychological feeling on comfortable seats. Also, 43 human-interface elements (HIE's) such as seat height, seat width, seat depth, tilting angle, seat surface etc. were investigated. HIE was generally defined as the physical characteristic of manufacturing goods, and it had close related to the body dimension of a user and environment that it was used.

• Journal of Information Technology Applications and Management
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• v.23 no.3
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• pp.49-59
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• 2016

Rapid technological advancements and widespread adoption of smart phones in recent years provide students with new opportunities for getting knowledge and making researches in innovation century. As the penetration of smart phone devices in education increases, there is a large growth in the use of these devices especially among the youth. In spite of increasing importance of smart devices in education, the significant features of these technology devices for general learning have not been experientially addressed. In this study we are going to investigate the comparison of smart phone devices and find the necessary conditions for using mobile devices as an educational tool by a conjoint method. There will be five attributes: screen size, batter type, mobile OS, memory capacity and price. By surveying we got the results which showed us the respondents' desire of using specific smart phone; thus, we defined that screen size attribute is the most important device characteristic.

• Proceedings of the KIEE Conference
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• 2003.07e
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• pp.87-91
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• 2003

Most of the loads in industrial power distribution systems are balanced and connected to three wires power systems. However, in the user power distribution systems, most of the loads are single & three phase and unbalanced, generating a large amount of non-characteristic harmonics. With the advent of power electronics and proliferation of non-linear loads in industrial power applications, power harmonics and their effects on power quality are a topic of concern. Harmonics by the unbalance voltage and non-linear loads, cause the increase of machine loss and heating. In order to allow current harmonic compensation, a filter must be installed. This paper describes the performance of passive filter under the voltage unbalance and non-linear load.

• Proceedings of the KIEE Conference
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• 2003.07b
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• pp.696-698
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• 2003

Most of the loads in industrial power distribution systems are balanced and connected to three wires power systems. However, in the user power distribution systems, most of the loads are single & three phase and unbalanced, generating a large amount of non-characteristic harmonics. With the advent of power electronics and proliferation of non-linear loads in industrial power applications, power harmonics and their effects on power quality are a topic of concern. Harmonics by the unbalance voltage and non-linear loads, cause the increase of machine loss and heating. In order to allow current harmonic compensation, a filter must be installed. This paper describes the performance of passive filter under the voltage unbalance and non-linear load.

• Korean Institute of Interior Design Journal
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• v.21 no.4
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• pp.121-128
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• 2012

Interactive space became one of the modern contemporary society design paradigms. For elevating the interactive effect, we need Interactive design development which uses the influential factors on the interactivity. Digital technology is resulted in a change to a society as well as to the life of human and its way of communication. This study is inquiry into the relations and the common characteristics between ecological architecture space and eco-centric environmental philosophy by making a comparative research. This aims to examine type of spatial contexts for performed through literature research for theory by interactive space and case studies for ecological construction elements to design. And the range of case study is limited to interaction space in addition of interactive elements and user interface. And analysis conclusion is show the many type. Five principles that draw at ecological design conceptualization process, whole unity, variety of organic at ecological design conceptualization process, circularity, homeostasis, allness, biological evolution, diversity have involved with concept that presents in ecological esthetics and organic property of ecology-system.

• The Journal of Information Systems
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• v.17 no.1
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• pp.83-111
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• 2008

The purpose of this study is to identify which factors are important for learning performance and the moderating effects of self-regulated factors such as elaboration and organization between users characteristic(perceived usefulness, preparatory education, internet experience) and learning performance. To Accomplish these research purpose, this study performed a survey and 173 response were used for statistical analysis. The results of this study are as follows: First, 7 factors(ease of use, interactivity, accuracy, media richness, perceived usefulness, preparatory education, internet experience) had significant impacts on learning performance whereas reliability did not. Second, the moderating effects of self-regulated factors showed that Elaboration of self-regulated factors can be considered as a significant moderating variable between 2 factors(perceived usefulness, internet experience) and teaming performance.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.2
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• pp.285-290
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• 2010

We investigate the outage probability in terms of QoS (quality of service) in indoor PLC network. We consider various kinds of appliances for realistic indoor PLC network. For estimation of the outage probability, we calculate the time-varying channel responses considering the loading conditions based on regular human activities and include the additive noise. We calculate the outage probability for each terminal and investigate relationship between the outage probability and the channel length, and transmit powers. Our results suggest that the outage probability is increased when the channel length becomes longer because more appliances affect the amount of reduced channel capacity and is not improved distinctly for very high and low outage threshold by increasing the transmit power. However, we can see outage probability improvement for 30% outage threshold case by increasing the transmit power.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.195-198
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• 2000

This paper have been analyzed performance of DS-CDMA/QPSK system in short range IVC, and evaluated packet uu rate(PER) in an On-Ray Rician channel model suitable for platoon driving of AVHS that 60GHz millimeter wave is very powerful to MP(multipath-wave). We analyzed probability characteristic of system as variation of Rician factor and user number in One-Ray Rician fading environment and evaluated packet error rate(PER) according to inter-vehicle distance when the BCH channel coding(255,247,1) and diversity schemes is adopted.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2255-2260
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• 2007

This Paper focuses on modeling and simulation to analyze the characteristic of hybrid vehicle. The system includes proton exchange membrane fuel cell(PEMFC), photovoltaic generator(PV), lead-acid battery, motor, vehicle and controller. Main electricity is produced by the PEMFC and battery to meet the requirements of a user load. When vehicle is parked in a sunny place, extra power is generated by the photovotaics and is charged in a battery for next drive. Further we evaluate usefulness of this hybrid vehicle by using ADVISOR - the advanced vehicle simulator written in the Matlab/Simulink environment. According to simulation results, the extra power obtained by photovoltaics which have been explored in nature conditions can help to reduce the electrical load of PEMFC and increase the efficiency (over 30%).