• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2014.10a
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• pp.176-178
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• 2014

해상 교통 관제 시스템을 구축하기 위한 센서 장치 중, 자동식별장치(AIS, Automatic Identification System)는 핵심적인 역할을 수행하는 센서 장치다. AIS가 제공하는 메시지 중 국제해사기구(IMO, International Maritime Organization) Circ.289 권고안의 6번 및 8번 메시지를 통한 ASM (Application Specific Message)은 선박위치송출이라는 AIS 고유 목적을 넘어 AIS 활용 범위를 확대시킨 좋은 예이다. 이에 본 논문에서는 AIS-ASM 서비스를 분석하여 해상 안전 분야에 적용할 수 있는 방안을 제시하고, 더 나아가 일부 AIS-ASM 서비스의 개선 방안을 소개하고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.391-392
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• 2012

항로표지의 원격 관리를 VHF, CDMA, TRS의 경로설정 최적화(Path Optimization) 기능을 갖는 하이브리드 통신을 이용하면 개별 통신 방식별로 음영지역이 존재하는 경우에도, 최적의 통신방식을 선택하여 통신을 수행하게 됨으로써, 통신 음영지역의 해소가 가능하다. 또한 통신장치마다 동일한 데이터 프레임을 사용함으로써 데이터의 호환성을 높였다. 실험은 30일 동안 각 부표에서 매 5분마다 데이터를 취득하였으며, 데이터 수신율은 99.4 % 이상을 보였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.84-85
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• 2013

AIS가 선박의 충돌방지를 통한 안전 확보뿐 만 아니라 육상과 선박간의 데이터 통신에 의한 선박과 선원 정보 관리, 전자해도 업데이트 등이 가능함이 입증되면서 국제해사기구를 중심으로 논의되고 있는 e-Navigation의 중요한 데이터 통신망으로 주목 받고 있다. 정보를 주고받는 프로토콜의 표현 형식은 비트중심의 메시지 표현 형태를 따르며 목적에 따라 다양한 메시지의 종류가 정의되어 있다. 이들 메시지 중 이진 메시지의 경우에는 사용자가 원하는 서비스에 따라 이진 메시지의 형식과 내용을 정의하여 다양한 정보를 주고 받을 수 있다. 본 논문에서는 AIS의 이진 메시지를 활용한 응용 서비스 프로파일로 AIS RF 모니터링 서비스를 제안한다.

• Journal of Advanced Navigation Technology
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• v.26 no.6
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• pp.404-411
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• 2022

The main function in operating the satellite navigation system is to accurately determine the orbit of the navigation satellite and transmit it as a navigation message. In this study, we developed software to determine the orbit of a navigation satellite by combining an extended Kalman filter and an accurate dynamic model. Global positioning system (GPS) and quasi-zenith satellite system (QZSS) orbit determination was performed using international gnss system (IGS) ground station observations and user range error (URE), a key performance indicator of the navigation system, was calculated by comparison with IGS precise ephemeris. When estimating the clock error mounted on the navigation satellite, the radial orbital error and the clock error have a high inverse correlation, which cancel each other out, and the standard deviations of the URE of GPS and QZSS are small namely 1.99 m and 3.47 m, respectively. Instead of estimating the clock error of the navigation satellite, the orbit was determined by replacing the clock error of the navigation message with a modeled value, and the regional correlation with URE and the effect of the ground station arrangement were analyzed.

• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.381-388
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• 2022

In 2021, development of a regional satellite navigation system called KPS was approved. In this regard, various studies are in progress, but there is no published signal model. So, in relation to the user segment, it is necessary to design a user receiver, but there is no information. Therefore, in this paper, we assume a signal model that can be a candidate signal for KPS based on related studies. This signal uses CNAV-2 structure navigation message, truncated Gold code and BPSK modulation. Based on this signal, a simulator is designed that can be used for receiver design later. The simulator consists of a signal generator and a signal transmitter, and is verified using a software receiver and spectrum analyzer.

• Journal of Advanced Navigation Technology
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• v.15 no.6
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• pp.939-945
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• 2011

We show a new scheme and implementation of maritime data communication systems for GMDSS ship which performs e-Navigation and removes the functional limitation of those systems through comparing to service fee, call processing reliability, and bit rates of all of those systems within communication range at sea. We confirmed available each frequency band communication and application services at sea by experimental result with proposed new system, MF/HF band being useful to a short text message service, VHF band to 9600bps email service, Fleet Broadband Maritime Satellite system to one or more Mbps multimedia service each.

• Journal of Advanced Navigation Technology
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• v.19 no.4
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• pp.265-277
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• 2015

Automatic dependent surveillance-broadcast (ADS-B) is the core technology of communication, navigation and surveillance/air traffic management (CNS/ATM), automatically broadcasts its own position information using GNSS and has an advantage of lower geological constraints and faster update speed compared with legacy radar systems. EUROCONTROL defined all purpose structured eurocontrol surveillance information exchange (ASTERIX) CAT.021. ASTERIX CAT.021 is modified several times, but it has compatibility issues with previous version of it. In this paper, we have designed an efficient message processing module regardless of the version of ASTERIX CAT.021. This implemented module generates patterns to collect messages received from the network, after that, received messages are processed in the routine that is defined in accordance with the patterns.

• Journal of the Institute of Convergence Signal Processing
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• v.14 no.2
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• pp.77-81
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• 2013

The international standard AIS, which stands for the safety of ship navigation and vessel traffic management, provides 27 messages to exchange the navigational information of ship. Among 27 messages, message ID 6 and 8 are defined as the binary data format to exchange application specific information and are classified into IFM for international use and RFM for national or regional use. Since international standards are based on English, there have been some needs to exchange data in Hangul text for vessel traffic management to correct the static and dynamic ships' information. In this paper, I analyze international standards to provide a Hangul text messaging service based on RFM and propose a RFM message and a simple protocol to correct information of a ship.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• v.2
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• pp.9-14
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• 2006

Galileo is the European Global Navigation Satellite System, under civilian control, and consists on a constellation of medium Earth orbit satellites and its associated ground infrastructure. Galileo will provide to their users highly accurate global positioning services and their associated integrity information. The elements in charge of the computation of Galileo navigation and integrity information are the OSPF (Orbit Synchronization Processing Facility) and IPF (Integrity Processing Facility), within the Galileo Ground Mission Segment (GMS). Navigation algorithms play a key role in the provision of the Galileo Mission, since they are responsible for computing the essential information the users need to calculate their position: the satellite ephemeris and clock offsets. Such information is generated in the Galileo Ground Mission Segment and broadcast by the satellites within the navigation signal, together with the expected a-priori accuracy (SISA: Signal-In-Space Accuracy), which is the parameter that in fault-free conditions makes the overbounding the predicted ephemeris and clock model errors for the Worst User Location. In parallel, the integrity algorithms of the GMS are responsible of providing a real-time monitoring of the satellite status with timely alarm messages in case of failures. The accuracy of the integrity monitoring system is characterized by the SISMA (Signal In Space Monitoring Accuracy), which is also broadcast to the users through the integrity message.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.272-274
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• 2015

Success of communication at sea is directly linked with clear and complete delivery and receipt of the target message between interlocutors. It can be said that speakers' effective delivery of their intended message and listeners' precise decoding and accurate understanding are the keys to successful maritime communication. From this perspective, the scope of maritime English education and training needs to be reconceptualized and expanded into the area of communication itself, beyond the simple acquisition of, and familiarization with, IMO Standard Maritime Communication Phrases (SMCP). Therefore, in order to make learners' acquisition of marine communication knowledge more feasible, and the knowledge learned more practically applicable, training on effective and clear oral delivery should be also considered within the frame of maritime English education. Thus, critical training elements to realize this goal need to be suggested as guidelines. In this presentation, the theoretical background on this will be introduced in terms of English as a Lingua Franca (ELF) and Lingua Franca Core (LFC), which are the current mainstream forms of English communication in the international business context. Based on this, six key training elements will be discussed; that is, speech rate, word groups, pauses, nuclear stresses, consonants (including consonant clusters), and vowels (specifically long and short vowels). Finally, the practical pedagogical methods of each element, and its actual application into a real ESP classroom, will be suggested.