• Title/Summary/Keyword: LRIT

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Analysis on Processing Timeline of COMS LHGS Design

  • Bae, Hee-Jin;Koo, In-Hoi;Seo, Seok-Bae;Ahn, Sang-Il;Kim, Eun-Kyou
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.216-219
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    • 2006
  • This paper analyzes on LHGS (LRIT/HRIT Generation Subsystem) processing timeline for COMS LHGS design. The LHGS shall transmit LRIT/HRIT (Low Rate Information Transmission/ High Rate Information Transmission) data to the users within 15 minutes after the end of the image acquisition. So, this paper performs experiment using MTSAT-1R LRIT/HRIT (11 days) and calculates minimum LHGS processing time. Only HRIT FD (Full Disk) image is considered in this paper because data size of HRIT FD image is the largest. As a result of experiment, COMS LHGS should be able to receive MI Level 1B product within 157 seconds at least.

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Robust ROI Watermarking Scheme Based on Visual Cryptography: Application on Mammograms

  • Benyoussef, Meryem;Mabtoul, Samira;El Marraki, Mohamed;Aboutajdine, Driss
    • Journal of Information Processing Systems
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    • v.11 no.4
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    • pp.495-508
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    • 2015
  • In this paper, a novel robust medical images watermarking scheme is proposed. In traditional methods, the added watermark may alter the host medical image in an irreversible manner and may mask subtle details. Consequently, we propose a method for medical image copyright protection that may remedy this problem by embedding the watermark without modifying the original host image. The proposed method is based on the visual cryptography concept and the dominant blocks of wavelet coefficients. The logic in using the blocks dominants map is that local features, such as contours or edges, are unique to each image. The experimental results show that the proposed method can withstand several image processing attacks such as cropping, filtering, compression, etc.

OVERALL LINK ANALYSIS ON HRIT AND LRIT IN COMS

  • Park Durk-Jong;Hyun Dae-Wan;Kang Chi-Ho;Ahn Sang-Il;Kim Eun-Kyu
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.98-100
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    • 2005
  • This paper describes link analysis on the processed data, HRIT (High Rate Information Transmission) and LRIT (Low Rate Information Transmission), for the preliminary design of interface between COMS (Communication, Ocean and Meteorological Satellite) and ground station. At the MODAC (MeteorologicaVOcean Data Application Center), the processed data are transmitted to user station via COMS with normalization and calibration by pre-processing of MI (Meteorological Imager) data. Due to consider satellite as radio relay, overall analysis containing uplink and downlink is needed. Specific link parameters can be obtained with using the outcomes of SRR (System Requirement Review) which was held on 13-14 June 2005, in Toulouse. From the relation between overall link margin and output power of HPA (High Power Amplifier) of MODAC, it is shown that even though the minimum power related with COMS receiving power range is transmitted at MODAC, the obtained link margin of HRIT could be above 3 dB at user station which antenna elevation angle is 10 degree.

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PERFORMING OF SOC DATS INTERFACE TEST WITH MODEM/BB

  • Park, Durk-Jong;Hyun, Dae-Hwan;Koo, In-Hoi;Ahn, Sang-Il;Kim, Eun-Kyou
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.64-66
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    • 2006
  • DATS will connect with IMPS and LHGS to perform the reception of sensor data and the transmission of user's meteorological data, LRIT and HRIT. MODEM/BB will perform the de-commutation of received sensor data as MI and GOCI raw data according to VCID before sending them to MI and GOCI IMPS, respectively. Especially, MODEM/BB in SOC needs to be connected to six clients that consist of the primary and backup IMPS of MSC, KOSC and SOC. On the other hand, LRIT and HRIT delivered from LHGS are encoded as VITERBI and modulated by MODEM/BB. Considering sensor data transmitted from COMS, the assumed format and size of CADU are described in this paper. Finally, results related to the status of received LRIT and HRIT by frame synchronizer in user station are also described.

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Survey on the Korean MCS Systems and Development Issues (국내 MCS 시스템 현황 및 발전 방향)

  • Kim, Geon-Ung;Park, Gyei-Kark;Choi, Jo-Cheon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.10
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    • pp.2019-2029
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    • 2009
  • There are several MCS(Monitoring, Control and Surveillance) systems for maritime safety and security in Korea; VMS (Vessel Monitoring System) that based on the AIS(Automatic Identification System), and the LRIT(Long-Range Identification and Tracking), the Vessel Free Pass System that based on the RFID(Radio Frequency IDentification), the Fisheries Information Network that provided by the National Federation of Fisheries Cooperatives. This paper surveys the fundamental technologies of MCS systems, and compares the role and function of them. It also surveys the development direction of each systems and research topics for cooperation of them.

Fingerprint Identification Based on Hierarchical Triangulation

  • Elmouhtadi, Meryam;El Fkihi, Sanaa;Aboutajdine, Driss
    • Journal of Information Processing Systems
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    • v.14 no.2
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    • pp.435-447
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    • 2018
  • Fingerprint-based biometric identification is one of the most interesting automatic systems for identifying individuals. Owing to the poor sensing environment and poor quality of skin, biometrics remains a challenging problem. The main contribution of this paper is to propose a new approach to recognizing a person's fingerprint using the fingerprint's local characteristics. The proposed approach introduces the barycenter notion applied to triangles formed by the Delaunay triangulation once the extraction of minutiae is achieved. This ensures the exact location of similar triangles generated by the Delaunay triangulation in the recognition process. The results of an experiment conducted on a challenging public database (i.e., FVC2004) show significant improvement with regard to fingerprint identification compared to simple Delaunay triangulation, and the obtained results are very encouraging.

효율적인 정보교환을 위한 해양정보통신시스템의 발전방안에 관한 연구

  • Jeong, Jung-Sik;Jeong, Jae-Yong;Kim, Cheol-Seung;Nam, Taek-Geun
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.2
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    • pp.113-118
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    • 2006
  • ECDIS의 이용과 함께 AIS, LRIT와 같은 선박식별 추적장치의 도입은 항해환경의 많은 변화를 유도하고 있다. 영국, 미국, 노르웨이, 일본 등 해운선진국들을 중심으로 전자항해의 전략개발에 관한 의제가 IMO MSC81차 회의에서 제안된 이후 2008년 MSC 제85차 회의까지 완료를 목표로 장기과제로 채택된 바가 있다. MSC 제81차 회의에서는 MAV.가 Coordinator로 하여 신규의제로 검토하도록 COMSAR 11 및 NAV 53차에 지시한 바가 있다. 본 연구에서는 국내 및 국외 전자항해 및 해양정보시스템의 동향분석을 통하여 효율적인 정보교환을 위한 해양정보통신시스템의 발전방안을 제시하였다.

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ANALYSIS ON PROCESSING PERFORMANCE OF COMS LHGS

  • Bae, Hee-Jin;Ahn, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.105-108
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    • 2007
  • The COMS LRIT/HRIT broadcast service should satisfy the 15 minutes timeliness requirement. The timeliness requirement is an important enough to impact on the overall performance of LHGS. Therefore, the simulation for the LHGS processing was performed with the LHGS prototype in this paper. First, processing time is measured for each process (per modules) of the LHGS without I/O time. Then, the LHGS processing is performed with worst scenario and the processing time is measured. Finally, analyses for processing time and time constraint are performed.

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COMS SOC 13M ANTENNA G/T MEASUREMENT

  • Park, Durk-Jong;Yang, Hyung-Mo;Ahn, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.489-492
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    • 2007
  • At COMS SOC, 13m antenna system will serve to transmit command and receive telemetry in S-Band for COMS operation. In addition, Sensor Data and LRIT/HRIT in L-Band will be received and LRIT/HRIT in S-Band will be transmitted through this antenna system. In many cases, G/T is used as barometer to estimate the receiving capability of antenna system. To estimate G/T, this paper presents two approaches, one is analysis based on the specification of antenna and RF equipment while the other is measurement by using Sun. From the results, G/T was proven as more than 20dB/K and it means that the required G/T, 19dB/K is verified successfully.

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VERIFICATION ON THE PERFORMANCE OF COMS SOC S-BANDSSPA

  • Park, Durk-Jong;Yang, Hyung-Mo;Ahn, Sang-Il
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.482-485
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    • 2007
  • The S-Band SSPA is front-end equipment to transmit both LRIT and HRIT to COMS. To provide the required EIRP, S-Band SSPA is designed to generate maximum 1kW power at its 1dB gain compression point (P1dB). Due to the operation for 24 hours per seven days, the verification on the performance of S-Band SSPA was performed thoroughly. This paper presents that major requirements such as maximum 1kW power, maximum -26dBc of IMD characteristic at 500W output and around -57dBc of coupling factor were verified through proposed test configuration.

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