• International Journal of Control, Automation, and Systems
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• v.6 no.5
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• pp.651-659
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• 2008

Autoreclosing techniques have been used in power systems to maintain system stability and continuity of supply. Environmental and economical issues have driven significant increases in the development of distributed generation (DG). DG connected to distribution systems, however, may impose negative influences with respect to power quality, protection, and stability, because DG can cause some challenges to protection, especially to reclosing. For this reason, in order to improve the reliability and safety of the distribution system, the rules and guidelines suggest that the DG system needs to be rapidly disconnected from the system before reclosing. We present, in this paper, an adaptive reclosing algorithm considering the DG. The algorithm consists of an angle oscillation's judgment, the emergency extended equal-area criterion (EEEAC), the calculation of an optimal reclosing time, and a reconnection algorithm. Our simulation results for three different DG technologies with Electromagnetic Transient Program (EMTP) indicate that we can maintain transient stability while the DG is protected against disturbances.

• Journal of the Korean Home Economics Association
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• v.33 no.1
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• pp.99-110
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• 1995

The purpose of this study was to provide basic material of positive effects on moral development through educational intervention between parent and chile reciprocal. The major findings were as follows: (1)Child's moral development level was a significant difference according to the level of socialization patterns. (2) Predictability of subvariables of socialization patterns revealed an order of mode of social control, role system and communication system. (3) Therer was a significant difference between stage 2 and the other of stages in socialization patterns. (4) There was a significant difference between stage 2 and stage P in role system. (5) There was no difference between stage 2 and the other of stages in communication system, mode of social control, IQ, and S.E.S.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09a
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• pp.1289-1293
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• 2010

A slipring or FORJ are usually adopted in order for power supply of Geo-centrifuge and input/output data acquisition. Since using slipring causes quite a lot electrical noise, an optical communication using FORJ becomes more general for data acquisition. Such data acquisition devices, however, require frequent maintenance and replacement due to deterioration by long term usage. DICT has set up a real-time wireless date acquisition system using wireless communication technology instead of FORJ. The system enables a remote measurement at any inertial acceleration field up to 100g level and provides as same performance as FORJ. The priority of this system is to use a normal modem substituting a special FORJ.

• International Journal of Internet, Broadcasting and Communication
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• v.7 no.2
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• pp.84-89
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• 2015

About 30% of Mongolian population is populated in the capital of the nation. Too many hospitals are concentrated in size as compared to the capital. This creates a difficult environment to provide equal distribution of medical benefit. In order to resolve this issue of medical benefit inequality, a portable/travelling medical treatment system using 'M-LIMS' is proposed for real-life application. The system with M-LIMS to be designed will include functions such as composing, sharing charts among doctors, standardizing charts. M-LIMS will be designed considering Mongol's regional characteristics, and application plans will be proposed accordingly.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.3-7
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• 2003

In this paper, radar scattering coefficients of earth surfaces such as grass fields, rice fields and bare soil surfaces are measured by using an auto-mounted network analyzer-based scatterometer system. The scatterometer system is calibrated both the magnitude and phase in order to obtain the accurate Mueller matrices of the earth surfaces. Then the accurate scattering matrices can be obtain from the Mueller matrices. The degree of correlation $\alpha$ is also obtained by this procedure and is used to correct AirSAR data which are not calibrated with phase variations.

• Journal of the Korea Computer Industry Society
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• v.10 no.3
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• pp.99-104
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• 2009

In this paper, fluorescent lamp on/off control and luminous intensity used an power line communication and remotely will be able to control system design. Embodied the respectively illumination equipment and tools by the network using PLC. In order to remote control and on/off of illumination equipment, luminous intensity composed a server. Will convert a previous analog system with digital system and the possibility witch will reduce an error ratio was. Consequently will be able to simplify a circuit.

• Journal of Advanced Navigation Technology
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• v.11 no.2
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• pp.170-176
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• 2007

In this paper, we improve performance for system when the carrier recovery signal is not perfect in the multipath mobile wireless communication fast fading channel based on DS-CDMA system. In the case, we use the phase estimation, diversity and adaptive FEC code technique in order to overcome this carrier phase error and mobile wireless fading. As a results in DS-CDMA system, we know that the appropriate use of diversity and adaptive FEC code technique reduced considerably performance degradation due to phase error.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.853-855
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• 2013

In this paper, we proposed the store monitoring system using smart hanger. This system consists of smart hanger, server, and wireless communication module. The smart hanger consists of LCD, MCU, RF module. In order to verify the effectiveness of the proposed smart hanger, we performed the experiment. This smart hanger can be used for shopping mall to increase sales.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.55-56
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• 2018

In order to reduce the risk of accidents, we proposed a construction safety management system combined with wearable device and LoRa (Low-Range Wireless Network) communication method to apply the usefulness of Internet (IoT) technology which means "everything connected". to construction safety management Management system. The proposed wearable safety device is a device that relays information exchange between wearable safety device and safety management server by LoRa wireless communication method. The safety management server can store workers bio-data and perform big data analysis. If a risk factor is determined from the analysis result, a warning is sent to the wearable safety device and the manager's application. The goal of this system is to prevent construction workers from entering the dangerous area that is not suitable for work, and to prevent safety accidents caused by human cause by detecting abnormal condition during work.

• ETRI Journal
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• v.35 no.4
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• pp.722-725
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• 2013

In this letter, a wireless communication system with microdiversity and macrodiversity reception in gamma-shadowed Rician fading channels is considered. Exact and rapidly converging infinite-series expressions for the average level crossing rate and average fade duration at the output of the system are provided. Numerical results are presented graphically to illustrate the proposed mathematical analysis and to examine the effects of the system's parameters on the quantities considered.