• Journal of the Korean Society of Visualization
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• v.5 no.2
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• pp.26-32
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• 2007

Stereoscopic PTV and Stereoscopic-PIV measurements have been carried out for the studies of the wake of a ship's propeller. Stereoscopic photogrammetry based on a 3D-PTV principle was introduced using two high-definition cameras(1k x 1k, 30Hz). The arrangement of the two cameras was based on angular position. The pair-matching of the three-dimensional velocity vectors were based on Genetic Algorithm based 3D-PTV technique. The results obtained by both measurement systems have been compared at the advance ratio J=0.88(290 rpm, d=54 mm). Turbulent properties have also been compared each other at the same condition.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.10a
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• pp.270-272
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• 2015

선박의 항해 도중 GPS 위성을 이용하여 위치를 추정하는 방법이 널리 사용되고 있다. 본 연구에서는 재밍으로 인하여 항해 중에 간헐적인 GPS 신호의 획득은 가능하나 지속적인 신호 추적이 불가하여 GPS 위성의 코드 위상 측정치만 얻을 수 있는 상황을 가정하였다. 동 시간대의 기준국에서 수신한 항법 메시지와 신호 획득 과정에서 측정된 코드 위상 만을 이용하여 GPS C/A 코드의 반복 횟수를 정확히 추정하고 대략적인 위치 해를 계산하는 알고리즘을 개발하였다.

• Information and Communications Magazine
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• v.16 no.9
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• pp.28-41
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• 1999

위상배열 안테나 시스템에서 빔 제어 기술은 이동통신 및 위성통신시스템, 비행하고 있는 임의의 비행체의 위치를 고도의 정확도를 가지고 추적하는 군사용 레이더 시스템이나 항공사의 통신 시스템, 선박이나 차량간의 충돌을 방지하기 위한 충돌방지 시스템 등에서 널리 사용되고 있다. 이러한 위상배열 안테나 시스템에서 위상천이기를 이용하는 방법이 널리 사용되고 있다. 이 방법은 원리적으로 간단하지만 실제 구현할 때 위상천이기를 제어하기 위한 제어 신호와 DC 바이어스 라인들 그리고 전력분배기로 구성되어 있기 때문에 전체 회로가 복잡해진다. 뿐만 아니라 현재로서는 위상천이기의 가격과 삽입 손실 때문에 저렴하고 높은 이을 갖는 위상 배열 안테나 시스템을 구현하기가 힘들다. 본 논문에서는 위상천이기를 사용하지 않고 발진기들의 결합을 이용함으로써 이와 같은 단점을 극복하면서 배열 안테나의 복사 빔을 제어할 수 있는 결합발진기 배열 안테나의 최근 기술동향을 분석하고 여러 기술들의 장단점을 기술한다.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.2
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• pp.192-198
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• 2013

This paper presents the stabilization and design of a pan-tilt control part for the directional pan-tilt system for shipboard directional equipment. In order to control each control axis with compensation for ship motion, the 2 degree of freedom(2DOF) PID controller is designed and its parameters are tuned using a real-coded genetic algorithm(RCGA). Simulation demonstrates the effectiveness of the 2 DOF PID controller tuning.

• Proceedings of the Korea Information Processing Society Conference
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• 2022.11a
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• pp.1062-1064
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• 2022

해외로 이동하고 있는 컨테이너 화물의 실시간 위치를 확인하고 기상정보 및 국제 이슈 등을 고려하여 도착 예상 시간을 계산해 화물의 도착 예정시간을 실시간으로 확인할 수 있는 서비스이다. 그동안 선박 추적 시스템은 해외 서비스에 의존해왔으며, 선사에서 자체적으로 제공하는 정보는 정확도가 40%에 미치는 한계가 존재했다. 이러한 문제점을 보완하여, 해당 서비스를 통해 빅데이터 기반의 분석과 향후 프로젝트 운영을 통해 축적될 시스템 상의 데이터와 현장의 데이터를 취합하여 높은 정확도를 이룰 수 있을 것으로 예상한다. 이를 통해 수출 기업들은 안전재고를 감축할 수 있게 되어 보관 관련 물류비용을 절감할 수 있게 될 것이다. 또한 보다 정확한 제조 일정을 수립할 수 있게 되어 과잉 생산을 방지할 수 있음을 기대해볼 수 있다.

• The Journal of the Korea institute of electronic communication sciences
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• v.12 no.3
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• pp.411-418
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• 2017

In the domestic case, although technological capabilities are recognized globally in the IT field, it is actually that the technical capabilities of the domestic leisure ship market which is formed mainly by fishing vessels are not beyond their technical capabilities At the point where the GNP of our country already goes over 22,000 dollars, the demand for the products related to the middle and small leisure boats is gradually increasing, but most of the high added value products depend on the imports from U.S.A. and Europe. And in case of the cars, with the Car Navigation as the start, products which satisfies various demands of the users are coming out in large quantity and now the IT technology is the necessity which can not be lived without in the car industry. Thus, if the digital ship navigator which jointed the recent ICT technology which was applied to the land for the domestic middle and small leisure ships by utilizing the embedded hardware technology and mapping technology which are credible is developed and distributed, it will become not only the opportunity to improve the industry related to middle and small ship IT, but also, the export about overseas market can be expected.

• Journal of the Korea Society of Computer and Information
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• v.16 no.9
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• pp.69-76
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• 2011

According to the related reports, about 60 percents of ship collisions have resulted from operating mistake caused by human factor. Specially, the report said that negligence of observation caused 66.8 percents of the accidents due to a human factor. Hence automatic detection and tracking of an object from an IR images are crucial for safety navigation because it can relieve officer's burden and remedies imperfections of human visual system. In this paper, we present a method to detect an object such as ship, rock and buoy from a sea IR image. Most edge directions of the sea image are horizontal and most vertical edges come out from the object areas. The presented method uses them as a characteristic for the object detection. Vertical edges are extracted from the input image and isolated edges are eliminated. Then morphological closing operation is performed on the vertical edges. This caused vertical edges that actually compose an object be connected and become an object candidate region. Next, reference object regions are extracted using horizontal edges, which appear on the boundaries between surface of the sea and the objects. Finally, object regions are acquired by sequentially integrating reference region and object candidate regions.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.39 no.3
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• pp.218-229
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• 2003

A new biotelemetry method that the installation and the treatment of equipment is convenient and the instantaneously detailed location of the fish attached the pinger is able to track comparatively easily was developed. The receiving system in this biotelemetry method was advanced for track the detailed behavior of the fish by the miniature tracking pinger, because it was a burden to fish to add the pinger with the water temperature and the pressure sensor. By combining of the super short base line (SSBL) method to detect the direction of pinger and the pinger synchronizing method to measure the range from receiving transducer to pinger, the three dimensional locations of fish to the receiving transducer is gotten instantaneously. The receiving system is devised to realize the high precision or wide detection range by application of the basic design method for receiving system of biotelemetry developed by the present authors and the hydrophone array configuration. The measurement distance error in the pinger synchronizing method is minimized through the correction of which the deviation of transmission pluse period of pinger is caused by changing water temperature. A prototype system which is able to track the instantaneously detailed location of the fish by the SSBL and pinger synchronizing biotelemetry (SPB) method was produced.

• Journal of Navigation and Port Research
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• v.36 no.10
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• pp.883-888
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• 2012

Recently, the logistics industry in Asia is growing rapidly mostly with Chinese economic development. A variety of studies have been carried out to reduce the logistic cost under the situation that the global freight traffic continues to increasing. The Short Sea Shipping(SSS) system, a multi modal transport system centered around coastal shipping to realize high value-added logistics, achieved considerable success in EU. To implement the SSS system in Korea, it is necessary to develop the various essential technologies related to development of efficient ships and port facilities, including equipment for loading and unloading containers, operating and managing systems for freight terminals and technologies for tracking and securing containers. The present paper focuses on the survey of the current essential technologies available for implementation of the SSS system and suggests the direction of future development in the technologies.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.29 no.1
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• pp.273-277
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• 2005

In this paper, we study on adaptation of the kalman filter for FDS(fishery detection system) to protect and aquaculture farms. The FDS will detect a robbing vessel with real time and a variance of the position of fishing fields. The kalman filter for tracking system that can be detect and track the approaching object without mounting F-AIS(Fishery Automatic Identification System) is applied. Some simulation results for the acceleration object with white noise is showed and the possibility of adaptation for tracking system is discussed.