• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.8
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• pp.1251-1258
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• 2002

The weather FAX machine is the one of necessary of safety navigation for ship. which is the machine which make the weather image by the receiving radio signal which is modulated using FSK method and transmitted on air by coast station. after Coast station scan the weather image and broadcast the image with black dot to 1500Hz and white dot to 2300Hz using FSK modulation. This paper implement weather fax machine using only general IBM-PC by software. By using IBM-PC we can make some good functions like print, edit, save etc. The modulated signal from SSB go into RS232C port via photo coupler not to give damage to PC. by using Timer Interrupt and RS232C serial interrupt, we can measure signal frequency and remake weather image. This paper use only IBM-PC with general SSB receiver which is widely spread on the ship. so this is very economic and possible to implement mutifunctions.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2010.04a
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• pp.555-556
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• 2010

연안 수역에서의 해상교통 환경변화에 부응하고 나아가 대형 해양사고 방지와 인명사고 예방을 위해 필요한 해양기상신호표지 시스템 구축을 위하여 해양기상 관측 및 항로표지 정보제공 시스템을 도입, 통항선박에게 안전항해에 필요한 정보를 제공함으로서 해양교통 안전을 확보하고자 한다. 인천 연안의 팔미도를 포함한 15개 항로표지시설에 기상(온습도, 풍향/풍속, 기압) 및 해양(유향/유속, 수온, 파고/파향) 관측시스템을 설치하고 항로표지용 AIS (AtoN AIS) 통신시스템을 이용하여 육상 정보수집 처리서버 및 항행 선박에게 해양기상관측자료를 실시간 전송하는 시스템을 구축하였다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.380-382
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• 2012

목포, 진도, 인천, 대산 및 여수권역에 설치된 해양기상신호표지시스템은 지속적이고 안정적인 데이터 확보와 데이터 Quality 유지가 중요하며 상시적인 현장점검 및 유지관리가 수반되어야 한다. 정기적이고 체계적인 유지관리를 통하여 주변 환경으로부터 장비를 보호하고 관측정보의 신뢰성을 높이고 장비 장애 및 오류를 사전에 방지할 수 있다. 관측자료의 효율적인 활용을 위하여 홈페이지, ARS/FAX, SMS 등의 서비스를 통합관리하고, 통합품질관리 기술개발 및 서비스 체계 표준화를 통하여 범국가적인 해양기상관측서비스 체계 구축이 필요하다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.853-856
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• 2007

A weather radar extracts the weather information from the return echoes which consist of scattered electromagnetic wave signals from rain, cloud and dust particles, etc. The acquisition of accurate weather information depends on the operation environment which include the Doppler weather signal and ground clutter characteristics. Since the conventional symmetric weather Doppler model does not represent the measurements in real situations, the improved model is suggested to describe the skewness in the Doppler spectrum model. Using the suggested model, many various weather signals can be simulated to verify the accuracy of signal processing algorithms and the reliability of the extracted weather information

• Journal of the Korea Institute of Information and Communication Engineering
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• v.13 no.9
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• pp.1753-1759
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• 2009

A weather radar as one of the remote sensing devices to analyze the weather phenomena receives the return echoes which consist of scattered electromagnetic wave signals from rain, cloud and dust particles, etc. These received Doppler weather spectra are analyzed to extract the various characteristic weather information. The mean wind velocity is one of the important weather parameters which can be obtained by a weather radar ed it may be useful in the prevention of weather hazards occurred by the abrupt shift of wind in small geographical scales such as microbursts. It is usually estimated by pulse pair method which is considered to be reliable and very efficient in the computational requirement. However, there are some problems in the accurate estimation of the mean velocity if Doppler spectra of weather signals appear to be asymmetric gaussian or multi-peak spectra. Therefore, in this paper, the problems in the mean estimation of asymmetric Doppler spectra are analyzed and the improved method is suggested.

• Aerospace Engineering and Technology
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• v.3 no.2
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• pp.133-140
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• 2004

In some cases, the launch vehicle is fatally affected by the change of weather condition. Thus the real time monitoring of weather condition is indispensible for successful launch campaign. This paper described general characteristics of weather radar for space center. The analysis of weather radar requirements has been carried out focusing on the transmitting power, gain of antenna, half power beam width, and minimum detectable signal.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.2
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• pp.19-28
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• 2018

In this paper, we studied on the sampling of ocean meteorological data to analyze signature of naval ships. The newest ocean meteorological data, that was quality controled by the Korea Meteorological Administration(KMA), was collected. Outliers were removed from the data by setting the usable range of data. After that, the data size was reduced through the random sampling method, taking geopolitical significance and effective area of buoy, for probabilistic analysis. Moreover, the sample sizes were set at 100, 200, and 400 by considering the population size and a 95% confidence level. The final sample was obtained using the two-dimensional stratified sampling method based on highly correlated water temperature and air temperature. The sum of the squared errors and the confidence interval was calculated to compare the result of sampling. As a result, this study proposed reasonable sample size for infra­red signature analysis of naval ships.

• The Journal of the Korea institute of electronic communication sciences
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• v.14 no.1
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• pp.61-68
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• 2019

In addition to non-meteorological echoes, meteorological echoes with large scattering effects, such as precipitation, cause errors in wind data measured by wind profiler. In the rainfall situation, the Doppler spectrum of wind profiler shows both the rainfall signal and the atmospheric signal as two peaks. The vertical radial velocity is very large due to the falling rain drop. The radial velocity contaminated by rainfall decreases the accuracy of the horizontal wind vector and leads to inaccurate weather analysis. In this study, we developed an algorithm to process raw data of wind profiler and distinguished rainfall signal and wind signal by partitioning bimodal peak for Doppler spectrum in rainfall environment.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.11 no.3
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• pp.452-458
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• 2007

Since there are very strong clutter returns in an airborne weather radar used for the detection of low altitude weather hazards, the reliable weather data cannot be extracted from the weak Doppler weather signal without cancellation of these strong clutter returns. However, the system phase noise spreads both the clutter and Doppler signal and causes the serious problems in the efficient clutter cancellation. Therefore, in this paper, the phase noise effects on the clutter and Doppler weather signal were analyzed. The system phase noise model was suggested and the effects were derived and explained using this phase noise model. It can be shown that there exists the limit in the clutter cancellation capability to improve the signal-to-clutter ratio (SCR) due to the system phase noise. It may be prominent especially in the low SCR situations.

• Journal of Astronomy and Space Sciences
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• v.24 no.4
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• pp.409-416
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• 2007

The ambiguity and performance of range measurement for COMS using tone standard was analyzed with assuming that satellite is operating at transfer-station and on-station. From the results of analysis, it was shown that the ambiguity was reduced when low frequency ratio between tone signals and large number of minor tones are applied. It was also found that using the narrow noise bandwidth leads to decrease the ambiguity. As a result, required performance of range measurement for COMS can be satisfied when the noise bandwidth is set as 2Hz for transfer-station and 1Hz for on-station, respectively.