• Information and Communications Magazine
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• v.25 no.10
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• pp.42-49
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• 2008

본고에서는 센서네트워크 기술의 역사와 배경 그리고 국방분야에 적용 가능한 센서네트워크 시스템에 대해서 기술한다. 국방 센서네트워크 시스템은 다른 센서네트워크 응용분야에 비해 유선 망 및 이동통신망 시스템에서 요구하는 신뢰성 있는 정보전달, 실시간 지원 등을 요구하고 있으며 또한 다중센서를 복합적으로 이용하여 적의 침입 또는 이벤트 발생을 100% 탐지하고 오보율 낮출 수 있는 기능을 요구한다. 본고에서는 이러한 국방 센서네트워크 시스템에서 요구하는 사항들을 만족시키기 위해 시스템의 주요 구성 요소들에서 수행해야 할 기술들, 센서 신호처리 및 식별 기술, 신뢰성 있는 패킷 전달을 위한 섹터안테나 및 섹터안테나 기반의 MAC 기술 그리고 실시간과 신뢰성 보장을 위한 라우팅 기술에 대해 논의한다.

• Proceedings of the KIPE Conference
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• 2014.07a
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• pp.251-252
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• 2014

본 논문은 직접토크 제어에서 토크와 자속 오차에 따라 결정된 전압 벡터가 가지고 있는 자속 및 토크 출력 특성을 전압의 d-q 해석을 통해서 분석하고, 6섹터 방식과 12섹터 방식에서 각 전압에 의해 발생되는 토크 및 자속 특성을 회전자 위치에 따라 해석하였다. 또한, 전압벡터의 전압특성을 모의하기 위한 근사 전압함수를 제시하고, 근사전압함수를 통해 직접토크 제어 방식에서의 자속 및 토크 제어의 성능향상이 가능함을 실험을 통해 검증하였다.

• Proceedings of the Safety Management and Science Conference
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• 2008.11a
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• pp.475-489
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• 2008

1987년 최초의 ISO 9000 (품질경영시스템) 패밀리 규격이 발행된 이래, 기업의 경영 시스템(Management System)의 핵심이 되는 MS 규격으로서 QMS(ISO 9001), EMS(ISO 14001), ISMS (ISO/IEC 27001) 등이 발행 또는 개정되어 왔다. 또 QMS 섹터 규격인 항공 우주 (AS/EN 9100), 의료기기 (ISO 13485), 정보통신 (TL 9000), ITSMS(ISO 20000), FSMS (ISO 22000), SCSMS (ISO 28000) 등이나 새로운 MS 규격이 되는 GHG(ISO 14064), IPOCM(ISO/PAS 22399), SR(ISO/CD 26000) 등 ISO 또는 비ISO 의 MS 규격이 차례차례로 발행 또는 개발 중에 있어 경영시스템 인증은 더욱 더 광범위해지면서 다방면화, 섹터화의 경향을 나타내고 있다. 제품 및 서비스 무역의 글로벌화, 조달 및 투자의 비 지역화, 공공 서비스에 대한 규제 철폐, 소비자 및 환경보호에 대한 공적인 요구, 테러리즘 전염병 자연적인 재앙에 대한 국제적인 연대 책임에 대한 필요성, 새로운 기술과 혁신의 전개 등이 경영 시스템 인증에 대한 요구를 증대시키고 있으며, 그 전제로서 세계적 규모로 제도의 신뢰성을 확보하는 구조의 확립 및 활동 결과의 신뢰가 보증되는 체제가 구축되어 있어야 한다. 이러한 신뢰를 바탕으로 한 제3자 인증제도는 세계경제의 원활한 발전에 중요한 과제가 되고 있다.

• Railway Journal
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• v.17 no.3
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• pp.11-17
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• 2014

• The magazine of the Korean Society for Advanced Composite Structures
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• v.2 no.4
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• pp.13-23
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• 2011

• The Journal of the Acoustical Society of Korea
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• v.21 no.8
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• pp.766-771
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• 2002

In this study, we have developed a 3-dimensional diagnostic ultrasonic sector probe using a convex type ultrasonic probe with 128 active elements. The probe was made to operate at the center frequency of 4.5㎒ with the bandwidth of 66%. The driving part was designed to rotate the axis of the convex probe by means of a step motor equipped with reduction gears and spur gears attached to the motor so that the probe could enable us to acquire a series of 2-dimensional images to construct a 3-dimensional image. Acoustic cover of the probe was made of polymers to have the same radius of rotation as that of the convex probe. The controllability of the rotation angle and the structural stability of the probe were confirmed through experimental 3-dimensional images obtained using the developed 3-dimensional sector probe.

• Journal of the Korean Vacuum Society
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• v.20 no.1
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• pp.1-6
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• 2011

A sudden step change is observed in the vertical position readings from beam position monitors (BPMs) mounted at the several sector vacuum chambers of Pohang Light Source. To study the source of this sudden step change, we measured the RF transmission scattering matrix (S21) through the pickup electrodes of BPMs mounted at the both ends of the sector vacuum chamber. The measured $S_{21}$ graph of the sector vacuum chambers suffering sudden step change has a peak in the BPM operation frequency bandwidth. Otherwise that of the other sector vacuum chambers doesn't have a peak. It is shown by the numerical simulation that the peak found in the BPM operation frequency bandwidth corresponds to the longitudinal harmonic of transverse electric resonance mode.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.451-456
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• 2005

This paper proposes an evaluation model to assessment of development and operation for maritime leisure in Mokpo Port.. The proposed model is combination of SWOT(Strength, Weakness, Opportunity, Threat) and AHP(Analytic Hierarchy Process) to evaluate development and operation for maritime leisure. The evaluation hierarchical structure is structured by ISM(Interpretive structural modeling) and composed of five level. At the third level, It combine SWOT into the assessment system. Strength and Weakness are internal factors. Opportunities and threats are external factors. There are economic and maritime leisure development in the model. There are three development and operation investment as Third-Sector, company, local organization. According to the results, the participants perceive prefer to strength and opportunity and found that the priority for the development and operation for maritime leisure of Third-Sector.

• Journal of Navigation and Port Research
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• v.29 no.8 s.104
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• pp.715-721
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• 2005

This paper proposes an evaluation model to assessment of development and operation for maritime leisure in Mokpo Port.. The proposed model is combination of SWOT(Strength, Weakness, Opportunity, Threat} and AHP(Analytic Hierarchy Process) to evaluate development and operation for maritime leisure. The evaluation hierarchical structure is structured by ISM(interpretive structural modeling} and composed of five level. At the third level, It combine SWOT into the assessment system Strength and Weakness are internal factors. Opportunities and threats are external factors. There are economic and maritime leisure development in the model. There are three development and operation investment as Third-Sector, company, local organization. According to the results, the participants perceive prefer to strength and opportunity and found that the priority for the development and operation for maritime leisure of Third-Sector.

• The KIPS Transactions:PartC
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• v.9C no.3
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• pp.439-444
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• 2002

In this paper, we present both the link budget analysis according to system parameters and the cell coverage according to transmitter power and modulation scheme of digital MMDS among the wireless CATV system methods which is bated on the wireless internet service. Also, in this paper, we present C/I and number of subscriber according to splitting cell. In this paper, the cell coverage of which obtain the results according to both transmitter power from 0dBW to -9dBW and modulation scheme of QPSK, 16QAM and 64QAM based on link budget was analysis for system parameter of digital MMDS was able to provide from maximum 134km to minimum 4.3km. Also, in this paper, the number of subscriber of which obtain the results according to polarization wave, frequency of frequency reuse and C/I in 4. 6 and 8 sectors was able to provide from maximum 5,200DSI to minimum 1,300DSI.