• Journal of the Institute of Electronics Engineers of Korea SP
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• v.47 no.4
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• pp.105-111
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• 2010

This paper proposes the recursive algorithm for passive proximity detection system based on signal strength. The system is designed to be used in the smart medicine chest in order to provide location-based service for the senior personnel. Due to the system profile, single receiver and uni-direction communication are applied over the signal attenuation model for the determination of user existence within certain proximity. The performance of conventional methods is subjective to the sight between the transmitter and receiver unless the direction of target is known. To appreciate the temporal and spatial locality of human subjects, the authors present exponential moving average (EMA) to compensate the unexpected position error from the direction and/or environment. By using optimal parameter, the experiments with EMA algorithm demonstrates 32.26% (maximum 40.80%) reduction in average of the error probability with 50% of consecutive sight in time.

• Journal of the Institute of Electronics and Information Engineers
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• v.53 no.8
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• pp.119-126
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• 2016

In this paper, we proposed the planar textile resonator for constructing wearable MR-WPT system and analyzed the characteristic of textile substrates used in resonators. The planar textile resonators were designed to resonate at 1-10 MHz. The loop and coil were fabricated planar structure on textile substrate using conductive materials. Polyester fiber and cotton widely used in real life were chosen as textile resonators for wearable applications and copper tape and silver paste were used for fabricating planar loop and coil on textile substrate. For comparison analysis on transfer efficiency according to the types of textile, transmitter and receiver parts were symmetric. According to the result, for the highest transfer efficiency of wearable WPT system, the planar resonators have specifications of relative thick textile substrate with low permittivity and low surface resistance of conductive pattern. The performed experiments show that the planar textile resonator is possible to be used for resonator in wearable MR-WPT system.

• Journal of Oral Medicine and Pain
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• v.34 no.1
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• pp.39-48
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• 2009

Recently there is much interest in the antibacterial activity of nano-sized silver particle (nanosilver) since silver is known to be safe and effective as disinfectant for a long time. Oral malodor is considered to originate in the oral cavity primarily as a result of production of malodorous compounds by oral bacteria. Major compounds responsible for oral malodor are volatile sulfur compounds, which is thought to be generated by the G(-) anaerobic bacteria found normally in the oral cavity, especially on the dorsum of the tongue. The purposes of this study were to investigate the effect of nanosilver on growth of oral malodor generating microorganisms, including Fusobacterium nucleatum, Prevotella melaninogenica, Klebsiella pneumonia, and to determine the optimal culture condition of them. The results were as follows: 1. The optimal culture condition for P. melaninogenica was vacuum culture using desiccator after evacuation of air by vacuum pump in chopped beef meat media. 2. The growth of K. pneumonia was temporarily inhibited by nanosilver (5 ppm and 10 ppm). 3. The morphological alteration and cell damage caused by nanosilver were observed in K. pneumonia.