• Atmosphere
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• v.24 no.3
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• pp.391-402
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• 2014

This study investigated the performances of precipitable water vapor (PWV) retrieval from the sets of ground global positioning system (GPS) signals, each of which had different length of observing-session duration, for the purpose of obtaining as short session duration as possible that is required at the least for appropriate retrieval of the PWV for meteorological usage. The shorter duration is highly desirable to make the most use of the GPS instrument on board the mobile observation vehicle making measurements place by place. First, using Bernese 5.0 software the PWV retrieval was conducted with the data sets of GPS signals archived continuously in 30 seconds interval during 2-month period of January and February, 2012 at Bukgangneung site. Each of the PWVs produced independently using different session durations was compared to that of radio-sonde launched at the same GPS location, a Bukgangneung site. Second, the same procedure was done using the data sets obtained from the mobile observation vehicle that was operating at Boseong area in Jeonnam province during Changma observation campaign in 2013, and the results were compared to that at Bukgangneung site. The results showed that as the observing-session duration increased the retrieval errors decreased with the dramatic change happening between 3 and 4 hours of the duration. On average, the root mean square error (RMSE) of the retrieved PWV was around 1 mm for the durations of greater than 4 hours. The results at both the Bukgangneung (fixed site) and Boseong (mobile vehicle) seemed to be fairly comparable with each other. From this study it is believed that at least 4 hours of observing-session duration is needed for the retrieval of PWV from the ground GPS for meteorological usage using Bernese 5.0 software.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.77-84
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• 2017

Recently, interest in safety has been increasing in every area, especially in the field of transportation. The accurate evaluation of the stability of road facilities is needed to improve the level of safety in the field of transportation and the application of new technologies is required to reduce the number of natural disasters. In this study, the wind data were compared and analyzed according to the type of measurement, and an evaluation of the stability of road signs using the wind data was conducted. In addition, a stability plan to secure road signs was elaborated and its effect on the wind load was analyzed. It was found that the wind data measured by a mobile atmospheric observing system (MAOS) was 2.43 times bigger than that measured by the Korea meteorological administration (KMA) and road weather information system (RWIS). In terms of their stability, the road signs were susceptible to failure caused by gusty winds and it was found necessary to ensure their stability. In the future, it will be possible to evaluate the stability of road facilities using road line weather data and the application of wind load reduction technologies is expected to improve road safety.