• Journal of Navigation and Port Research
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• v.34 no.4
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• pp.299-304
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• 2010

In this paper, the EM wave absorber was developed for the 94-GHz detecting radar system. To analysis an EM wave absorber in millimeter wave band, we fabricated three absorber samples using carbon black and titanium dioxide and permalloy with chlorinated polyethylene. After measuring the complex relative permittivity, the absorption characteristics are simulated by 1D FDTD according to different thicknesses of less than 1.0 mm. Then, the EM wave absorber was fabricated based on the FDTD simulation. As a result, the measured results agreed well with the simulated ones, and the developed EM wave absorber with a thickness of 0.7 mm had the desired absorption characteristics of more than 14 dB in the frequency range of the 94-GHz band.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.11a
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• pp.341-342
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• 2006

A physical model for reduction of Electromagnetic Interference(EMI) or its predecessors, Radio Noise, Electrical Noise, or Radio-Frequency-Interference(RFI), is a rapidly expanding digital technology. It covers the frequency spectrum from DC to about 3 GHz EMI is the poisoner which does not allow radio, TV, radar, navigation, and a lot of electrical, electro-mechanical, and electronic and communication devices, apparatus and systems to operate compatibly in a common frequency spectrum environment EMI can result in a jammed radio, heart pacer failures, navigation errors and many other either nuisance or catastrophic events. Therefore, it follows that this spectrum pollution problem has reached international levels of concern and must be dealt with m proportion to the safety and economic impact Involved.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.1
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• pp.89-93
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• 2009

This paper deals with obstacle avoidance for unmanned vehicle using stereo system. The "DARPA Grand Challenge 2005" shows that the robot can move autonomously under given waypoint. RADAR, IMS (Inertial Measurement System), GPS, camera are used for autonomous navigation. In this paper, we focus on stereo system for autonomous navigation. Our approach is based on Singh et. al. [5]'s approach that is successfully used in an unmanned vehicle and a planetary robot. We propose an improved algorithm for obstacle avoidance by modifying the cost function of Singh et. al. [5]. Proposed algorithm gives more sharp contrast in choosing local path for obstacle avoidance and it is verified in experimental results.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 1992.10a
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• pp.2-29
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• 1992

According to the increase of occupation density of microwave frequency band on use microwave environments have been congested extensively. For shielding unnecessary electromagnetic wave of preventing the electromagnetic wave reflection a good conductor a low resistive material or a lossy material is mainly used. As a method to measure the absorbing characteristics of microwave absorber the fundamental microwave measuring method can be used. There is however a big problem in measuring errors since the wavelength of microwave is very short especially as in the case as microwave absorber for RADAR. Therefore this research aimed to a converting adaptor of 20mm${\Phi}$ coaxial tube from a Type-N connector to 20mm${\Phi}$ coaxial tube and to use it for designing microwave absorber and evaluating absorbing characteristics. Furthermore the measurements of absorbing characteristics and material constants have performed and reviewed which were carried out by using the coaxial tube in the short type and by using rectangular waveguide respectively As a result the validity of the measured values have been confirmed.

• Journal of the Korean Institute of Navigation
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• v.16 no.4
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• pp.25-34
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• 1992

As a method of measure the absorbing characteristics of microwave absorber, the various microwave measuring method can be used fundamentally. There is, however, a big problem in measuring errors, since the wavelength of microwave such as used for radar is very short. Therefore, this research aimed to design and fabricate a converting adaptor of $20mm^{\phi}$ coaxial tube from a Type-N connector to $20mm^{\phi}$ coaxial tube and to use it for evaluating absorption characteristics of microwave absorber. Furthermore, the measurements of absorbing characteristics and material constants have been performed and review, which were carried out by using the coaxial tube and by using rectangular waveguide, respective. As a result, the validity of the proposed measuring method has been confirmed.

• Journal of the Korean Institute of Navigation
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• v.16 no.4
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• pp.35-45
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• 1992

In this study, an interface is developed in compliance with the standards which is made by National M.E.A in U.S.A for transmitting the Marine Gyrocompass information. The interface consists of Bearing Signal Transfer, Bearing Signal Demodulator, Bearing Signal Discriminator, Bearing Counter and, Informatioin Tranmitter. The results are as follows : The transmission of bearing information was achieved successfully on the Marine RADAR by the interface tranmitting for the Marine Gyrocompass. And, newly proposed phase-detector in Bearing Signal Discriminator which method is forcibly reset the previous data of D-T Flip Flop can be solved the problems of the delay in phase discrimination and the unstableness in the boundary areas of input signal.

• Journal of the Korean Institute of Navigation
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• v.22 no.2
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• pp.1-12
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• 1998

The fundamental objectives of vessel traffic services (VTS) are the safety of traffic, efficient traffic flow and the protection of marine environment. And the coverge of VTS is used to be within the port and their approaches. It , however, is tend to expand the coverge beyond the radar coverage and the vessel carrying dangerous cargo. Therefore this study aims to investigate the international tendancy of the extended VTS system, and take a field test of using KOREASAT for the extended VTS system in Korean coastal waters. As the results of the test, KOREASAT is proved to be one of the alternatives for extended VTS system.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.22-24
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• 2018

IT 발전과 함께 디스플레이가 탑재된 제품들을 주변에서 쉽게 찾아볼 수 있다. 제품의 디스플레이는 현재 상태 및 위험도 등 다양한 정보를 시각적으로 사용자에게 제공하는 중요한 역할을 하고 있다. 이로 인하여 시각적으로 사용자에게 좀 더 직관적이고 효율적으로 정보를 제공하는 방법에 대하여 많은 연구들이 진행되고 있으며, GUI 분야의 관심도 높아지고 있다. 항해분야에서 디스플레이가 포함된 항해장비는 RADAR, ECDIS, ODD 등 다양한 종류가 존재하며, 그 중에서 ECDIS가 가장 많은 시각적인 정보를 제공하고 있다. 이처럼 ECDIS는 항해사들에게 시각적으로 다양한 정보를 제공하는 중요한 장비로써 본 연구에서는 기존의 ECDIS의 요구사항을 조사하며, HCD를 고려하여 개선된 ECDIS 장비의 작업 수행도를 평가하였다.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2002.12a
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• pp.89-92
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• 2002

최근 들어 급증하고 있는 해양 충돌 사고 증가의 원인은 선박을 조종하는 항해사의 잘못된 판단 에 의한 부주의가 대부분이다. 이러한 문제를 해결하기 위한 가장 적극적인 방법은 선박에 자동화 및 지능화를 부여하여 항해사의 실수를 최소화하는 것이다. 대표적인 연구는 선박의 자율운항시스템(autonomous navigation system)이 있는데, 이는 선박운항에 있어 항해계획을 수립하고 현재의 선박의 상태를 파악하여 선박을 적절히 제어하는 항해 전문가시스템이다. 선박 자율운항시스템은 실세계의 선박에 장착되어 실험하여야하나, 선박은 고가의 운송수단이고, 자율운항시스템을 장착하기 위한 하부장치 인터페이스를 설계 및 구현에 많은 시간이 소요되므로 실제 선박을 모방하는 선박시뮬레이터를 이용하는 방법이 타당하다. 선박시뮬레이터는 선박의 물리적 운항특성을 모방하는 선박운동시뮬레이터와 선박 운항 주변에 변화하는 장애물을 시뮬레이터 하는 주변 객체시뮬레이터로 구성된다. 본 연구에서는 선박 운항 주변에 등장하는 장애물 변화를 시뮬레이션하고, 이에 기반한 ARPA RADAR를 모의 가동하는 주변객체시뮬레이터를 개발한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.06a
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• pp.407-410
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• 2013

2010년대에 들어서며 산업과 행정 등 전반 분야에 있어 주요한 아젠다가 되어 있는 빅 데이터는 산업화를 거쳐 전산화의 장벽까지 넘어선 각 분야에서 혁신적인 데이터 활용을 통해 새로운 가치를 창조하고 있다. RADAR 및 관제설비의 도입으로 고도화된 VTS의 관리 체계는 관제 서버의 구축과 선박의 선박자동식별장치(AIS)의 정착 등 항해설비 발전을 통해 전산의 장벽을 하나씩 거둬가고 있다. 이제는 실시간으로 수집되는 선박 교통 데이터를 통해 해사행정의 새로운 가치 창조를 모색해야 할 시점이다. 따라서 본 연구에서는 예시를 통해 빅 데이터의 개념을 정리하고 해상교통관제를 비롯한 해사행정 전반분야와 해운, 항만, 선박 사업자 전반에게 효율적인 업무 지원을 도모할 수 있는 모델을 제시하고자 하였다. 본 연구결과가 VTS 발전 방안으로 활용되어 제도 개선에 기여할 것으로 기대된다.