• Journal of Navigation and Port Research
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• v.33 no.10
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• pp.685-690
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• 2009

International Maritime Organization (IMO) recommends the installation of an Automatic Identification System (AIS) according to requirements by SOLAS to avoid maritime collision. AIS provides traffic information of other ships that may be used for maritime traffic control, SAR (Search and Rescue) and collision avoidance to apply safety management. In this paper, preliminary results to implement an aeronautical surveillance transceiver using AIS transceiver based on ADS-B concepts are described. Although altitude information is not required for AIS since the AIS is operated at MSL (Mean Sea Level), altitude information can be extracted by a GPS (Global Positioning System) chip-set in the AIS transceiver. ADS-B transceiver is implemented by defining a surveillance message format including the altitude information and modifying SOTDMA (Self-Organizing Time Division Multiple Access) protocol. Ground tests and flight tests are performed to validate the implementation results.

• Journal of Mechanical Science and Technology
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• v.17 no.5
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• pp.654-667
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• 2003

This paper presents a consequence of the systematic approach to identify the aerodynamic parameters of an unmanned aerial vehicle (UAV) equipped with the automatic flight control system. A 3-2-1-1 excitation is applied for the longitudinal mode while a multi-step input is applied for lateral/directional excitation. Optimal time step for excitation is sought to provide the broad input bandwidth. A fully automated programmed flight test method provides high-quality flight data for system identification using the flight control computer with longitudinal and lateral/directional autopilots, which enable the separation of each motion during the flight test. The accuracy of the longitudinal system identification is improved by an additional use of the closed-loop flight test data. A constrained optimization scheme is applied to estimate the aerodynamic coefficients that best describe the time response of the vehicle. An appropriate weighting function is introduced to balance the flight modes. As a result, concurrent system models are obtained for a wide envelope of both longitudinal and lateral/directional flight maneuvers while maintaining the physical meanings of each parameter.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1995.09a
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• pp.300-324
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• 1995

This research investigates the automatic identification of typical embedded structures in the Integer Programming(IP) models and automatic transformation of the problem to an adequate Lagrangian problem which can provide tight bounds within the acceptable run time. For this purpose, the structural distinctiveness of variables, constants, blocks of terms, and constraint chunks is identified to describe the structure of the IP model. To assist the identification of the structural distinctiveness, the representation by the knowledge based IP model formulator UNIK-IP is adopted. For the reasoning for the structural identification, the bottom-up, top-down, and case-based approaches are proposed. A prototype system UNIK-RELAX is developed to implement the approaches proposed in this research.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.19-20
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• 2009

International Maritime Organization(IMO) recommends the installation of an Automatic Identification System(AIS) according to requirements by SOLAS Chapter 5 to avoid maritime collision. AIS provides traffic information of other ships that may be used for maritime traffic control, SAR(Search and Rescue) and collision avoidance to apply safety management. In this paper, preliminary results to implement an aeronautical surveillance transceiver using AIS transceiver based on ADS-B concepts are described. Although altitude information is not required for AIS since the AIS is operated at MSL(Mean Sea Level), altitude information can be extracted by a GPS chip-set in the ALS transceiver. ADS-B transceiver is implemented by defining a surveillance message format including the altitude information and modifying SOTDMA protocol. Ground tests and flight tests are performed to validate the implementation results.

• The Journal of the Acoustical Society of Korea
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• v.37 no.3
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• pp.129-138
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• 2018

In port and coastal areas where ship traffic is frequent, ship noise dominantly influences underwater noise in low frequency band below 1 kHz. In this paper, we propose a modeling method to estimate the underwater shipping noise using the voyage information of ship observed in AIS (Automatic Identification System). For the purpose of ship noise modeling, the navigation information of the vessels operating in the southern part of Jeju was observed using AIS and underwater noise was measured by installing a hydrophone in the experimental area to verify the modeled ship noise. AIS data were used to model the noise level of ship and compared with measured underwater noise. The variation of noise level with time was found to be similar, and the cause of the error was discussed. Through this study, it was confirmed that the noise level of ship can be estimated within 5 dB error range using AIS data.

• Journal of Biosystems Engineering
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• v.24 no.1
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• pp.75-80
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• 1999

Signal separation and transmission are essential for automatic breeding management of domestic animals. Electronic identification system could transmit the signal of an individual within a defined range to a personal computer by an electromagnetic signal recognition method. Signals for individual recognition were originated by controlling 12 tri-state pins of IC(PT2262) in a transmitter. PT 2262 can generate 4,096 codes. These encoded signals were modulated and transmitted with wireless lines from the transmitter. Then they were demodulated in a receiver, and the signals were transmitted to the micro-processor through an interface and were identified in a PC.

• Journal of the Korea Safety Management & Science
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• v.8 no.4
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• pp.119-127
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• 2006

This paper deals with the middleware and S/W development of real time automatic attendance check management system using ubiquitous 900Mhz RFID(Radio Frequency Identification). This system supports the real time automatic attendance check and necessary data processing in class management. We expect to decrease the effort for class management and to upgrade the status of real time management of class.

• Proceedings of KOSOMES biannual meeting
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• 2005.11a
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• pp.59-64
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• 2005

The AIS(Automatic Identification System) is the useful equipment in order to promote the maritime safety and real time monitoring at the sea. In this study, the plan to construct the ubiquitous Aids to navigation is proposed In order to verify the construction of ubiquitous Aids to navigation, the experiment on the sea was carried out and analyzed.

• Journal of Navigation and Port Research
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• v.30 no.3 s.109
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• pp.197-201
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• 2006

The AIS(Automatic Identification System) is the useful equipment in order to promote the maritime safety and real time monitoring at the sea. In this study, the plan to construct the ubiquitous Aids to navigation is proposed. In order to verify the construction of ubiquitous Aids to navigation, the experiment on the sea was carried out and analyzed.

• Korean Journal of Remote Sensing
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• v.34 no.4
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• pp.579-590
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• 2018

Shipping of North Korea is not yet publicly well documented. Taedong River, the most important sea route of North Korea, is selected as a model study area to show how effectively a remote place can be investigated through the application of satellite-based Automatic Identification System (S-AIS) for understanding shipping and tracks of vessels which passed the lock gate in the Taedong River and visited the nearby ports on its track. S-AIS data of the year 2014 were analyzed on the basis of various time periods, country of registry and category of ships. A total of 325 vessels were observed. The ships under the flags of North Korea, Cambodia and Sierra Leone were found to be dominant in frequencies which accounted for 43.08%, 16.00%, and 8.92%, respectively. Trajectories of the 325 ships in the Yellow Sea were also checked according to the flags. It is concluded that some ships under the flags of Cambodia, Sierra Leone, Mongolia, Panama and Kiribati are regarded as flags of convenience, and ships without flag and ship type codes also comprised a remarkable portion out of the total ships.