• Proceedings of the Korea Information Processing Society Conference
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• 2010.11a
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• pp.648-651
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• 2010

웰빙의 바람을 타고 이제 자신의 건강을 관리하는 사람들이 많아지고, 흡연에 대한 좋지 않은 인식이 높아지면서 금연의 열풍이 강하게 불고 있다. 하지만 금연을 한다고 해도 주위의 담배연기는 우리 몸의 건강을 해치기 때문에 담배연기로부터 해방되기는 매우 어렵다. 실제로 흡연하는 배우자를 가진 사람은 그렇지 않은 사람에 비해 심장병 발생률은 40%, 폐암 발생률은 30%가 더 높다. 따라서 본 논문에서는 간접흡연이 인체의 조음기관에 미치는 영향을 분석하기 위해 간접흡연에 따른 음성의 변화를 측정하고 비교, 분석하는 실험을 수행하였다. 이를 위해 간접흡연 전과 후의 음성을 수집하여 음성분석학적 요소 기술 중 Pitch, Jitter, Shimmer 등의 성대 진동 요소를 적용하고 인체 내의 공명기관을 분석하는 Formant를 적용하여 실험을 수행하여 간접흡연이 음성에 미치는 영향을 연구하였다.

• ETRI Journal
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• v.35 no.1
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• pp.1-6
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• 2013

In this paper, we present an implemented serial 40-Gb/s receiver optical subassembly (ROSA) module by employing a proposed TO-CAN package and flexible printed circuit board (FPCB). The TO-CAN package employs an L-shaped metal support to provide a straight line signal path between the TO-CAN package and the FPCB. In addition, the FPCB incorporates a signal line with an open stub to alleviate signal distortion owing to an impedance mismatch generated from the soldering pad attached to the main circuit board. The receiver sensitivity of the ROSA module measures below -9 dBm for 40 Gb/s at an extinction ratio of 7 dB and a bit error rate of $10^{-12}$.

• ETRI Journal
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• v.35 no.1
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• pp.120-130
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• 2013

This paper presents an analysis of resource assignment for multihop communications in millimeter-wave (mm-wave) wireless personal area networks. The purpose of this paper is to figure out the effect of using directional antennas and relaying devices (DEVs) in communications. The analysis is performed based on a grouping algorithm, categorization of the flows, and the relaying DEV selection policy. Three schemes are compared: direct and relaying concurrent transmission (DRCT), direct concurrent transmission (DCT), and direct nonconcurrent transmission (DNCT). Numerical results show that DRCT is better than DCT and DCT is better than DNCT for any antenna beamwidths under the proposed algorithm and policy. The results also show that using relaying DEVs increases the throughput up to 30% and that there is an optimal beamwidth that maximizes spatial reuse and depends on parameters such as the number of flows in the networks. This analysis can provide guidelines for improving the performance of mm-wave band communications with relaying DEVs.

• Journal of Astronomy and Space Sciences
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• v.27 no.1
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• pp.11-20
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• 2010

This paper designs a data link between a Lunar Orbiter (LO) and an Earth Station (ES), and analyzes the downlink performance of a space communications system for lunar exploration, conforming to the recommendations by the Consultative Committee for Space Data Systems (CCSDS). The results provided in the paper can be useful references for the design of reliable communication link for the Korean lunar exploration in the near future.

• Proceedings of the Korean Information Science Society Conference
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• 2006.10c
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• pp.629-632
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• 2006

기존의 무선 네트워크에 비해 빠르고 저렴하며 설치가 편리한 무선 메쉬 네트워크를 인터넷망 구성에 도입하려고 하는 것이 최근의 경향이다. 무선 메쉬 네트워크는 이종망간의 네트워크를 통합함으로 수많은 클라이언트들을 통제해야하며 기존의 IPv4 주소는 10년 내에 고갈이 됨으로, IPv6 주소 환경에 적합하게 연구 개발하여야 한다. 그러나 아직 무선 메쉬 네트워크는 개발 중인 기술로써 보완해야할 보안상의 문제점들이 발견되고 있다. 본 논문에서는 무선 메쉬 네트워크에 MIPv6를 어떻게 도입할지를 언급하고 MIPv6 도입 시에 발생하게 되는 보안상의 문제점을 SEND(SEcure Neighbor Discovery)와 MCGAs를 이용하여 해결하는 방법을 소개한다.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.405-409
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• 2004

We chose the Kushiro wetland in Hokkaido, Japan, as a test site to monitor wetland areas. Synthetic aperture radar (SAR) can carry out continuous observation in any weather conditions, and can therefore be used to observe high humidity areas such as wetlands. We applied multi-parameter SAR data (dual-frequency, multi-polarization, and multi-incidence angle) to monitoring the wetland forest. To find the optimum incidence angle and polarization for monitoring the wetland biomass, a simple backscattering model of wetland vegetation was developed and applied to estimate backscattering coefficients for different biomass and surface conditions.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.170.4-170
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• 2001

Safety and confidence of the communications network is the main purpose for the unmanned control systems, in terms of appling a satellite communications network to the water treatment and supply plant communication system. Since the unmanned control systems were applied in the industrial site, the lack of confidence on the communications network has been presented continuously as a main problem for the unmanned and automation systems. Therefore, satellite communications network was presented as one of the methods to solve this problem, supporting the wire used telecommunication. In addition to the safety of a communications network, there is the retrenchment of expenditure. This dual communications network has ...

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.825-829
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• 2009

In this paper, we examine the fundamental performance of image coding schemes based on multipulse model. First, we introduce several kinds of pulse search methods (i.e., correlation method, pulse overlap search method and pulse amplitude optimization method) for the model. These pulse search methods are derived from auto-correlation function of impulse responses and cross-correlation function between host signals and impulse responses. Next, we explain the basic procedure of multipulse image coding scheme, which uses the above pulse search methods in order to encode the high frequency component of an original image. Finally, by means of computer simulation for some test images, we examine the PSNR(Peak Signal-to-Noise Ratio) and computational complexity of these methods.

• Journal of the Optical Society of Korea
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• v.9 no.2
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• pp.54-58
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• 2005

A novel mode analysis method and differential mode delay measurement technique for a multimode optical fiber based on optical frequency domain reflectometry has been proposed for the first time. We have used a conventional OFDR with a tunable external cavity laser and a Michelson interferometer. A few-mode optical multimode fiber was prepared to test our proposed measurement technique. The differential mode delay (DMD) of the sample fiber was measured to be 16.58 ps/m with a resolution of 1.5 ps/m. We have also compared the OFDR measurement results with those obtained using a traditional time-domain measurement method.

• Bulletin of the Korean Space Science Society
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• 2004.10b
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• pp.351-355
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• 2004

A multibeam switching satellite system technology have started localized development to overcome the limitation of the frequency resource and geostationary orbit existing relay type satellite transponder and the required performance of the spot beam, and looked around the configuration and functions of the multibeam switching satellite communication system. This paper proposed that operation scheme and network control features for service definition, network architecture, transmission method of the natural disaster service network and public communication service network using this system.