• Title/Summary/Keyword: The Republic of Korea

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Temporal and Spatial Wind Information Production and Correction Algorithm Development by Land Cover Type over the Republic of Korea (한반도 시공간적 바람정보 생산과 토지피복별 보정 알고리즘 개발)

  • Kim, Do Yong;Han, Kyung Soo
    • Journal of Korean Society for Geospatial Information Science
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    • v.20 no.3
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    • pp.19-27
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    • 2012

  • Wind is an important variable for various scientific communities such as meteorology, climatology, and renewable energy. In this study, numerical simulations using WRF mesoscale model were performed to produce temporal and spatial wind information over the Republic of Korea during 2006. Although the spatial features and monthly variations of the near-surface wind speed were well simulated in the model, the simulated results overestimated the observed values as a whole. To correct these simulated wind speeds, a regression-based statistical algorithm with different constants and coefficients by land cover type was developed using the satellite-derived LST and NDWI. The corrected wind speeds for the algorithm validation showed strong correlation and close agreement with the observed values for each land cover type, with nearly zero mean bias and less than 0.4 m/s RMSE. Therefore, the proposed algorithm using remotely sensed surface observations may be useful for correcting simulated near-surface wind speeds and producing more accurate wind information over the Republic of Korea.

  • https://doi.org/10.7319/kogsis.2012.20.3.019 인용 PDF KSCI

Experimental Analysis to Derive Optimal Wavelength in Underwater Optical Communication Environment (수중 광통신 환경에서 최적 파장을 도출하기 위한 실험적 해석)

  • Dong-Hyun Kwak;Seung-il Jeon;Jung-rak Choi;Min-Seok Han
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.16 no.6
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    • pp.478-488
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    • 2023

  • This paper investigates the naval application of laser communication as a potential replacement for traditional acoustic wave communication in underwater environments. We developed a laser transceiver using Arduino and MATLAB, conducting a water tank experiment to validate communication feasibility across diverse underwater conditions. In the first experiment, when transmitting data through a laser, the desired message was converted into data and transmitted, received, and confirmed to be converted into the correct message. In the second experiment, the operation of communication in underwater situations was confirmed, and in the third experiment, the intensity of light was measured using the CDS illuminance sensor module and the limits of laser communication were measured and confirmed in various underwater situations. Additionally, MATLAB code was employed to gather data on salinity, water temperature, and water depth for calculating turbidity. Optimal wavelength values (532nm, 633nm, 785nm, 1064nm) corresponding to calculated turbidity levels (5, 20, 55, 180) were determined and presented. The study then focuses on analyzing potential applications in naval tactical communication, remote sensing, and underwater drone control. Finally, we propose measures for overcoming current technological limitations and enhancing performance.

  • https://doi.org/10.17661/jkiiect.2023.16.6.478 인용 PDF HTML