• The Journal of the Korea institute of electronic communication sciences
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• v.6 no.2
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• pp.274-279
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• 2011

To increase the performance of mobile communication systems, base statations having beamforming function are released recently. For the proper beamforming function, it is required that each RF paths be calibrated periodically. However, the current calibration method has a problem when the base station is connected to a repeater. In this paper, we report the problem and propose a new calibration method to solve the problem.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.9
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• pp.999-1004
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• 2014

This intelligent keyboard instrument self learning system developed in this study consists of smartphone based learning application and keyboard-instrument auxiliary module. The keyboard instrument auxiliary module receives playing information of the instrument through smartphone application and bluetooth communication. Then the module shows it through LED display so that the relationship between the keyboard and scale could be easily recognized even for beginners. Also, this system provides saving function and analyzing function of user's performance data, making learning more effective.

• Journal of Communications and Networks
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• v.14 no.3
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• pp.237-242
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• 2012

One of the major problems for accurate channel estimation in power line communication systems is impulsive noise. Traditional channel estimation algorithms are based on the assumption of Gaussian noise, or the need to locate the positions of impulsive noise. The algorithms may lose optimality when impulsive noise exists in the channel, or if the location estimation of impulsive noise is inaccurate. In the present paper, an effective channel estimation algorithm based on a robust cost function is proposed to mitigate impulsive noise. The proposed method can provide a closed-form solution, and the application of robust estimation theory enables the proposed method to be free from localization of impulsive noise and thus can guarantee that the proposed method has better performance. Simulations verified the proposed algorithm.

• Proceedings of the KOSOMBE Conference
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• v.1995 no.05
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• pp.42-44
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• 1995

The original DANTE sequence and its variations have limitation in excitation profile (a sinc function-like excitation) due to the finite duration of the DANTE pulsetrain. This sinc function-like selection profile excites only a small fraction of the spins in the pixel thereby results in poor signal to noise ratio (only about ${\sim}1%$ of normal MR imaging sequence). Therefore, this poor signal to noise ratio (SNR) has been the main drawback of the original DANTE sequence. To improve the signal to noise ratio, phases of individual RF pulses in the DANTE pulse train were modulated so that more spins in the object were excited ($1{\sim}3$). We have introduced a new FM (Frequency Modulation) DANTE sequence and analyzed the signal intensity and excitation profiles.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.6
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• pp.1087-1092
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• 2017

This paper describes a work that makes convenient use of room indicator of a professors' office. The functions are divided into two main functions, the main function being the display panel and the additional function LCD display. Both of these functions are designed to be controlled by smart phone application using bluetooth wireless communication.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1736-1739
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• 2002

The advanced in semiconductor, hardware, and software technologies enables the integration of more com- plex systems and the increasing design complexity. As system design complexity becomes more complicated, System-level design based on the If block and processor model is more needed in most of the RTL level or low level. In this paper, we present a novel approach fur the system-level design, which satisfies the various required constraints and an optimization method of image encoder based on codesign of function, algorithm, and architecture. In addition, we show an MPEG-4 encoder as a design case study. The best tradeoffs between algorithm and architecture are necessary to deliver the design with satisfying performance and area constraints. The evaluations provide the effective optimization of motion estimation, which is in charge of an amount of performance in the MPEG-4 encoder module.

• Proceedings of the Korea Information Processing Society Conference
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• 2002.11b
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• pp.1317-1320
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• 2002

We present in this paper a new version of AODV that incorporates with "Minimizing Maximum node cost" by formulating that metric as a cost function of residual energy of nodes. An additional parameter is added to the cost function to consider the routing performance along with power-efficiency. The motivation of adding that new parameter is originated from the trace off between power-saving behaviors and routing performance.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.3
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• pp.339-343
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• 2010

In this paper, the energy saving illuminator with a function of crime and fire prevention is developed. This illuminator is communicated with a superintendent's office by wireless communication and the informations being archived by the illuminator are transmitted to a superintendent's office. If this illuminator is established with only one in a lecture room or a office room, a wireless network with saving a energy and preventing crimes and fires can be constructed.

• Proceedings of the KIPE Conference
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• 2010.11a
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• pp.345-346
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• 2010

The HVAC(Heating Ventilation and Air Conditioning) system is only controlled by turn on/turn off operations against to AC 380V input. Therefore, the efficiency of the system is reduced and noise occurs. Also, the blower is shut down at the AC power failure. In this paper, the inverter system with UPS function for the A/C(Air Conditioning) blower is proposed. Proposed inverter system which is powered from the AC and DC voltage can control speed, operation mode, and soft-start time using CAN communication. In case of the CAN communication failure, RS-232 communication could be used to control the hardware directly by the engineer that can solve existing problems. To verify the validity of proposed inverter system, simulations and experiments are carried out.

• International Journal of Advanced Culture Technology
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• v.10 no.1
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• pp.122-130
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• 2022

In modern times, text has become an image, and typography is a style that is a combination of image and text that can be easily encountered in everyday life. It is developing not only for the purpose of conveying meaningful communication, but also to bring joy and beauty to our lives as a medium with aesthetic format. This study shows through case analysis that typography is a tool for expressing human emotions, and investigates its characteristics that change along with the media. In particular, interactive communication tools and methods used by interactive typography to express viewers' emotions are described in detail. We created interactive typography using the inputted text, the selected music by the viewer and the viewer's movement. As a result of applying it to the exhibition, we could confirm that interactive typography can function as an effective communication medium that shows the utility of both the iconography of letter signs and the cognitive function when combined with the audience's intentional motion.