• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 춘계학술발표회 논문집
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• pp.69-74
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• 2003

GPS/Meteorology technique for PWV monitoring is currently actively being researched an advanced nation. But, there is no detailed research on an evaluation of precision of GPS derived PWV measurements during the period of foul weather condition. Here, we deal with the precision of GPS derived PWV during the passage of Typhoon RUSA. Typhoon RUSA which caused a series damage was passed over in Korea from August 30 to September 1, 2002. We compared th tropospheric wet delay estimated from GPS observation and radio-sonde data at four sites(Suwon, Kwangju, Taegu, Cheju). The mean standard deviation of PWV differences at each site is ${\pm}$0.005mm. We also obtained GPS PWV at 13 GPS permanent stations(Seoul, Wonju, Seosan, Sangju, Junju, Cheongju, Taegu, Wuljin, Jinju, Daejeon, Mokpo, Sokcho, Jeju). GPS PWV time series shows, in general, peak value before and during th passage of RUSA, and low after the RUSA. GPS PWV peak time at each station is related to the progress of a typhoon RUSA. We obtained very similar result as we compare GMS satellite image with tomograph using GPS PWV and we could present th possibility of practical use by numerical model for weather forecast.

• 한국측량학회지
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• 제21권1호
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• pp.9-17
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• 2003

한반도에 막대한 피해를 입힌 태풍 RUSA는 2002년 8월 30일에서 9월 1일간 한반도를 지나갔다. 이 태풍 RUSA가 진행하는 동안 GPS 수신 자료와 기상 자료를 이용하여 대류권에서의 습윤 지연량을 산출하고, 이 습윤지연량을 천정방향의 수증기량(IWV)으로 환산하여 이 수증기량으로부터 PWV(Precipitable Water Vapor)를 산출하였다. 본 연구에서는 서울, 원주, 서산, 상주, 전주, 청주, 대구, 울진, 진주, 대전, 목포, 속초, 제주의 13개 GPS 상시관측소 데이터를 이용하여 PWV를 산출하였다. 산출한 PWV의 시계열 분석을 통해 실제 강수량과 비교한 결과 태풍 RUSA가 진행하는 동안 PWV가 정점을 보이는 부근에서 실제 강수량이 발생하였다. 또한, 태풍 RUSA의 이동 경로와 PWV가 최고조를 이루는 시간을 분석한 결과 밀접한 관계가 있음을 알 수 있었다. GPS 자료로부터 산정된 PWV를 이용하여 tomograph를 작성하고 GMS 위성 영상과 비교한 결과 매우 근접한 결과를 얻을수 있었으므로 기상 예보를 위한 수치예보모델로의 활용 가능성을 제시할 수 있었다.

• 대한임상검사과학회지
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• 제48권4호
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• pp.378-387
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• 2016

심혈관계 위험인자를 비침습적으로 분석할 수 있는 PWV에 관한 다수의 선행연구에서 의견이 분분하고, 결과에 대한 일관성이 부족한 부분을 재현하고자 연구에 임하였으며, 더욱이 날로 증가하고 있는 노인을 대상으로 운동참여 여부와 성별에 따른 노인의 말초동맥파속도(baPWV), 신체구성과 심혈관계 변인의 상관성 및 재변인의 차이를 검증하는데 연구의 목적이 있다. 규칙적인 운동을 수행해온 노인남성 39명(이하, 운동군M) 과 운동을 수행해 오고 있지 않은 동일 연령대의 노인남성 38명(이하, 통제군M), 규칙적인 운동을 수행해온 노인여성 40명(이하, 운동군F) 과 운동을 수행해오고 있지 않은 동일 연령대의 노인여성 37명(이하, 통제군F)을 대상으로 변인에 대한 상관성과 집단별 재변인들 간의 차이를 알아본 결과 노인남성 운동군의 baPWV range와 근육량(r=0.357, p=0.026), 수축기혈압(r=0.468, p=0.003), rbaPWV (r=0.406, p=0.010), lbaPWV (r=0.333, p=0.038)가 통계적으로 유의한 상관관계를 보였고, 노인남성 통제군의 경우는 baPWV range와 심박수(r=0.395, p=0.014), rbaPWV (r=0.598, p=0.000), lbaPWV (r=0.602, p=0.000)가 유의한 상관성을 보였다. 노인여성 운동군은 baPWV range와 진단명(r=0.321, p=0.044), 수축기혈압 (r=0.399, p=0.011), 이완기혈압(r=0.545, p=0.000), rbaPWV (r=0.648, p=0.000), lbaPWV (r=0.676, p=0.000)가 유의한 상관성을 보였고, 노인여성 통제군 경우는 baPWV range와 나이 (r=0.471, p=0.003), rbaPWV (r=0.836, p=0.000), lbaPWV (r=0.801, p=0.000)가 통계적으로 유의한 상관성을 보였다. 반면 말초동맥파속도 변인 중 통계적으로 유의한 차이를 보인 그룹은 없는 것으로 나타났고, 요둔위($F_{3,150}=9.197$, p=0.000), 근육량($F_{3,150}=74.295$, p=0.000), 체지방율($F_{3,150}=35.045$, p=0.000), 수축기 혈압($F_{3,150}=3.525$, p=0.017)이 통계적으로 유의한 차이를 나타냈다. 본 연구에서는 집단별 특성에 따라 다양한 결과가 나타난다는 사실을 알 수 가 있었으며, 신체구성 변인과 심혈관계 변인 중 수축기 혈압은 운동 여부에 따라 민감한 변화와 차이를 보인 것으로 보아 노인의 경우 운동그룹은 신체구성과 심혈관계 일부 변인에 변화를 줄 수 있다고 단정지어 볼 수 있겠으나, 위팔-발목 맥박파전파속도에 대해서는 일관된 결과가 도출되지 않아서 이에 대한 지속적인 연구가 필요한 것으로 사료된다.

• Journal of Astronomy and Space Sciences
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• 제29권3호
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• pp.295-303
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• 2012

In this study, we compared the precipitable water vapor (PWV) data derived from the radiosonde observation data at Sokcho Observatory and the PWV data at Sokcho Global Positioning System (GPS) Observatory provided by Korea Astronomy and Space Science Institute, for the years of 2006, 2008, 2010, and analyzed the radiosonde seasonal, diurnal bias according to radiosonde sensor types. In the scatter diagram of the daytime and nighttime radiosonde PWV data and the GPS PWV data, dry bias was found in the daytime radiosonde observation as known in the previous study. Overall, the tendency that the wet bias of the radiosonde PWV increased as the GPS PWV decreased and the dry bias of the radiosonde PWV increased as the GPS PWV increased. The quantitative analysis of the bias and error of the radiosonde PWV data showed that the mean bias decreased in the nighttime except for 2006 winter, and in comparison for summer, RS92-SGP sensor showed the highest quality.

• 대한한방부인과학회지
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• 제23권1호
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• pp.53-64
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• 2010

Purpose: This study was performed to observe the correlation between Hot flush and pulse wave velocity(PWV), ankle brachial index(ABI) in the Climacteric women. Methods: We studied 63 climacteric women visiting OO hospital from 8th January 2007 to 22nd April 2009. The subjects were categorized in two groups, the hot flush group(37) and normal group(26). For the study, the subjects were selected by excluding the patients who receive treatment affect hot flush or have disease affect arterial states. We assessed PWV and ABI of two groups by Oscillometric method using VS-1000(Form PWV/ABI; Fukuda Denshi, Co., Ltd., Japan). From these results, we studied the correlation between hot flush and PWV/ABI by Wilcoxon Mann Whitney Test. Results: 1. It is shown that hot flush group was no significant correlation with normal group. There is no significant factor among R-PWV, L-PWV, R-ABI, L-ABI. However, L-ABI have shown relatively higher correlation with comparison to the other factors.(p-value<0.05) 2. R-PWV, L-PWV significantly increased in menopause group than in premenopause group though there is no relation to the hot flush. (p-value<0.01) Conclusion: Though the results showed no correlations between Hot flush and PWV/ABI in the Climacteric women, L-ABI showed relatively higher correlation with hot flush than others. R-PWV, L-PWV showed significant correlation between premenopause and menopause.

• Journal of Positioning, Navigation, and Timing
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• 제4권2호
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• pp.87-95
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• 2015

In this study, the temporal and spatial variation in precipitable water vapor (PWV) was analyzed for typhoon Ewiniar which had made landfall in the Korean peninsula in 2006. To make a contour map of PWV, zenith total delay (ZTD) was calculated using about 60 GPS permanent stations in Korea, and the pressure and temperature data of nearby AWS stations were interpolated and applied to the equation for calculating the PWV. While Typhoon Ewiniar was migrating north from the southern coast to the eastern coast of Korea, the PWV migrated showing a spatial distribution similar to that of rainfall. Also, the fluctuating pattern of the normalized PWV was analyzed, and the moving speed of the PWV was estimated using the delay time of the increase/decrease pattern in the eight-test stations. The result indicated that the moving speed of the PWV was about 35 km/h, which was similar to the average moving speed of the typhoon (38.9 km/h).

• Journal of Astronomy and Space Sciences
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• 제27권4호
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• pp.367-375
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• 2010

In this study, we compared the precipitable water vapor (PWV) data derived from the radiosonde observation data at Sokcho Observatory and the PWV data at Sokcho Global Positioning System (GPS) Observatory provided by Korea Astronomy and Space Science Institute, from 0000 UTC, June 1, 2007 to 1200 UTC, May 31, 2009, and analyzed the radiosonde bias between the day and the night. In the scatter diagram of the daytime and nighttime radiosonde PWV data and the GPS PWV data, dry bias was found in the daytime radiosonde observation as known in the previous study. In addition, for all the rainfall events, the tendency that the wet bias of the radiosonde PWV increased as the GPS PWV decreased and the dry bias of the radiosonde PWV increased as the GPS PWV increased was significantly less distinctive in nighttime than in daytime. The quantitative analysis of the bias and error of the radiosonde PWV data showed that the mean bias decreased in the second year, regardless of nighttime or daytime rainfall, and the non-rainfall root mean square error (RMSE) was similar to that of the previous studies, while the rainfall RMSE was larger to a certain extent.

• 대한한방내과학회지
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• 제30권3호
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• pp.525-533
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• 2009

Objectives : There are lots of reports that cardiovascular disease, including hypertension, cerebro-vascular accident, and coronary heart disease, is related to atherosclerotic changes. Increased serum levels of lipids could play a role in these changes. This study aimed to investigate the relationship between PWV and risk factors of cardiovascular disease, including serum lipid values. Methods : This study included 261 subjects ($49.32{\pm}11.79$ years, 112 male) who underwent PWV and serum lipid evaluation. We investigated the correlation between serum lipid values, blood pressure, body mass index (EMI) and PWV. Pearson's correlation and partial correlation analysis were applied to examine the relationship between PWV and risk factors of cardiovascular disease. Results : Serum triglyceride, total cholesterol, systolic blood pressure, and diastolic blood pressure were significantly correlated with PWV. Partial correlation coefficient adjusted by age yielded significant correlation between serum triglyceride, systolic blood pressure, diastolic blood pressure and PWV. Conclusion : In this study, it seems that there are significant relationships between PWV, triglyceride and blood pressure. We could suggest that PWV might have some relationships with Dam-eum and blood stasis in oriental theory.

• Spatial Information Research
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• 제18권4호
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• pp.33-41
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• 2010

우리나라에는 100여개의 GPS 상시관측소가 설치되어 있으나 대략 10개의 관측소만이 GPS 전용 기상센서를 보유하고 있다. 따라서 전국을 대상으로 하는 GPS 가강수량 산출을 위해서는 주변 AWS의 가상자료 보간에 의한 GPS 관측소 기상정보의 생성이 필요하다. 이 연구에서는 가상자료 보간 방법인 역해면경정과 크리깅의 보간 정확도를 분석하였다. 그 결과 역해변경정법의 RMSE가 기압의 경우 약 7배, 기온의 경우 약 2배 더 정확함을 확인하였다. PWV 정확도 분석을 위해 역해면경정법으로 보간된 기상자료와 GPS 관측자료를 이용해 2008년 여름철에 대한 GPS PWV를 산출하였다. 보간 기상 자료를 이용한 GPS PWV를 GPS 전용 기상센서의 값을 사용한 PWV, 라디오존데 PWV와 비교하였다. 비교 결과 보간 기상자료를 이용한 GPS PWV 가 요구 정확도 3mm이내를 만족함을 확인하였다.

• 한국측량학회지
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• 제36권1호
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• pp.33-39
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• 2018

As the retrieval accuracy of PWV estimates from GPS measurements is proportional to the accuracy of water vapor WMT, the WMT model is a significant formulation in the conversion of PWV from the GPS ZWD. The purpose of this study is to develop a MWMT model for the retrieval of highly accurate GPS PWV using the radiosonde measurements from six upper-air observing stations in the region of Korea. The values of 1-hr PWV estimated at four GPS stations during one year are used to evaluate the validity of the MWMT model. It is compared to the PWV obtained from radiosonde data that are located in the vicinity of GPS stations. Intercomparison of radiosonde PWVs and GPS PWVs derived using different WMT models is performed to assess the quality of our MWMT model for Korea. The result in this study indicates that the MWMT model is an effective model to retrieve the enhanced accurate GPS PWV, compared to other GPS PWV derived by Korean annual or global WMT models.