• ETRI Journal
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• v.38 no.3
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• pp.560-567
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• 2016

To solve the problem of parameter optimization in image sensor-based visible light positioning systems, theoretical limits for both the location and the azimuth angle of the image sensor receiver (ISR) are calculated. In the case of a typical indoor scenario, maximum likelihood estimations for both the location and the azimuth angle of the ISR are first deduced. The Cramer-Rao Lower Bound (CRLB) is then derived, under the condition that the observation values of the image points are affected by white Gaussian noise. For typical parameters of LEDs and image sensors, simulation results show that accurate estimates for both the location and azimuth angle can be achieved, with positioning errors usually on the order of centimeters and azimuth angle errors being less than $1^{\circ}$. The estimation accuracy depends on the focal length of the lens and on the pixel size and frame rate of the ISR, as well as on the number of transmitters used.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.22-26
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• 2004

In the light of necessary analysis on the cooperation and development between ports and shipping line, and the characteristic of cooperation between international ports and shipping lines, the article analyses the operating strategies in actual shipping lines benefits to the cooperation between ports and shipping lines. After all-round analysis on the cooperation and development between ports and shipping lines, the author presents the running model of ports and shipping lines in Far East, which is the integration of operation between ports and shipping lines (namely integration of logistics service network). (omitted)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2013.10a
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• pp.329-331
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• 2013

아국에서는 무상지원(ODA) 사업으로 캄보디아 항로표지시설 개발에 관한 마스터 플랜을 수립하고, 항로표지 장비 및 인력파견을 통하여 캄보디아 통항선박의 안전운항, 재산보호 및 해양환경을 보호하고, 항로표지이용료(Light Due) 징수제도 도입을 추진하여 캄보디아 정부 세수 확대시키어 항로표지시설 운영에 대한 자립기반을 마련하고자 함.

• Journal of Aerospace System Engineering
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• v.2 no.1
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• pp.17-21
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• 2008

A compact, light-weight, integrated flight control computer(IFCC) for small unmanned autonomous vehicles is developed. Its design objective is to produce an all in one avionics system which includes the navigation sensor, data link, attitude sensors and air data sensors. The initial phase of ground and flight tests are performed to verify the prototype IFCC, showing promising results. The high potential of its application is expected.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.1
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• pp.467-477
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• 2006

최근 조명기술의 발달에 따라 가장 각광을 받고 있는 것이 LED 소자를 이용한 발관체이다. 이미 육상의 교통신호등 뿐만 아니라, 차량 방향지시등, 빽라이트등 다양한 용도로 사용되고 있으며, 해상에도 등부표의 광원용으로 사용되고 있다. 이러한 추세에 맞추어, 항을 진입하는데 가능 필요한 도등의 광원용으로 LED를 사용하고 이를 제어하는 기술을 연구개발하여 전세계에서 처음으로 부산 신항에 설치하여 효과를 분석하였다.

• Journal of the Korean Institute of Navigation
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• v.24 no.4
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• pp.285-298
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• 2000

The purpose of this study is to shed some light on how market orientation, mediators such as employee satisfaction, service quality and commitment, and business performance are related and to offer important managerial implication for managements or marketing practioners in the International logistics service industry.

• Journal of the Korean Institute of Navigation
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• v.18 no.4
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• pp.171-178
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• 1994

Fiber optic gyroscopes must be a promising technology that can replace conventional mechanical ones based on the principle of inertia of spinning masses. The advantages of fiber optic gyroscopes over mechanical ones include low cost, light weight, compact size and fast turn-on time. We will apply them to fiber optic gyrocompass for ships. Fiber optic gyrocompass for ships requires the north-seeking accuracy of $15^{\circ}$/hr, earth rotation rate, or better. This article introduces the fiber optic gyroscope as rotation sensor in the fiber optic gyrocompass system for ships that is planed to develop in our laboratory.

• Journal of Navigation and Port Research
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• v.43 no.6
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• pp.361-368
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• 2019

Aid to Navigation (AtoN) is the artificial facilities to facilitate the ship's safe navigation using light, shape, color, sound, and radio waves. IALA has developed and operated the educational course for expert groups for the design, deployment, and management of AtoN. Also, maritime educational institutes have operated various educational courses for safe navigation through the ship's operation and ECDIS curriculum for seafarers. However, education using the AtoN Simulator System is needed to prevent marine accidents caused by misunderstanding of the AtoN according to various topographical, environmental, and maritime traffic environments. In this study, the existing ship handling simulator and AtoN simulator were applied to develop educational modules for accurate understanding and application of AtoN in various environments, enhancing the quality of education from the existing theoretical point of view and improving practical use to maximize educational efforts.

• Journal of the Korean Institute of Telematics and Electronics
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• v.26 no.7
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• pp.30-41
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• 1989

In this paper, a robust and simple structured light sensory system has been studied to endow mobile robots with the ability of navigating in real world. A mobile robot with this sensor can be applied in two ways: first, real time navigation in 3-dimensional world, second, modeling and recognition of environment. Range data obtained with this sensor are fairy accurate, and the data aquisition speed is satisfactory. Experiments in diverse situation show effectiveness of the structured light sensor for the mobile robot.

• Proceedings of the KIEE Conference
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• 2004.11a
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• pp.261-263
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• 2004

This paper studies the lighting pattern control of a high-brightness LED warning light. The driving circuit for the warning light is composed of a full-wave rectified circuit and of a control circuit using a micro-controller (AT89c2051). The micro-controller is programmed in a suitable manner to accomodate a number of variable lighting patterns and to adjust the blinking speed. To reduce the total number of LEDs installed a special consideration is made to the bundled pattern in a lamp module which is lit simultaneously. The resultant LED warning light has merits not only over the conventional incandescent warning light on the energy saving aspect but also over some other LED-type ones in the market.