• 제목/요약/키워드: field observation

검색결과 1,640건 처리시간 0.03초

Spatial correlation-based WRF observation-nudging approach in simulating regional wind field

  • Ren, Hehe;Laima, Shujin;Chen, Wen-Li;Guo, Anxin;Li, Hui
    • Wind and Structures
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    • 제28권2호
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    • pp.129-140
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    • 2019
  • Accurately simulating the wind field of large-scale region, for instant urban areas, the locations of large span bridges, wind farms and so on, is very difficult, due to the complicated terrains or land surfaces. Currently, the regional wind field can be simulated through the combination of observation data and numerical model using observation-nudging in the Weather Research and Forecasting model (WRF). However, the main drawback of original observation-nudging method in WRF is the effects of observation on the surrounding field is fully mathematical express in terms of temporal and spatial, and it ignores the effects of terrain, wind direction and atmospheric circulation, while these are physically unreasonable for the turbulence. For these reasons, a spatial correlation-based observation-nudging method, which can take account the influence of complicated terrain, is proposed in the paper. The validation and comparation results show that proposed method can obtain more reasonable and accurate result than original observation-nudging method. Finally, the discussion of wind field along bridge span obtained from the simulation with spatial correlation-based observation-nudging method was carried out.

Central nervous system depressant activity of Leucas aspera root

  • Rahman Shafiur;Sarder Mokaddez;Ali Yusuf;Rashid Abdur
    • Advances in Traditional Medicine
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    • 제6권3호
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    • pp.174-178
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    • 2006
  • The ethanolic extract of Leucas aspera root was studied for its effect on the central nervous system (CNS) using pentobarbitone induced sleeping time test, the open field test and the hole cross test in Swiss albino mice. The present investigation revealed that the extract at the doses of 250 and 500 mg/kg, significantly prolonged the pentobarbitone induced sleeping time in mice though the onset of sleep was delayed as compared to control. In open field test the depressing effect was prominent from the second observation period (30 min) and persisted throughout the entire experimental period (240 min). In the hole cross test, the depressing effect was observed significant from the third observation period (60 min) and persisted up to the seventh observation period (240 min) except at fourth observation (90 min) for 250 mg dose group and depressing effect was significant from second observation (30 min) up to seventh observation period (240 min) for 500 mg dose group. These results support the finding that Leucas aspera root may contain biologically active constituent(s) having CNS activity.

DETERMINATION OF USER DISTRIBUTION IMAGE SIZE AND POSITION OF EACH OBSERVATION AREA OF METEOROLOGICAL IMAGER IN COMS

  • Seo, Jeong-Soo;Seo, Seok-Bae;Kim, Eun-Kyou;Jung, Sung-Chul
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume I
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    • pp.228-231
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    • 2006
  • In this paper, requirements of Meteorological Administration about Meteorological Imager (MI) of Communications, Ocean and Meteorological Satellite (COMS) is analyzed for the design of COMS ground station and according to the analysis results, the distribution image size of each observation area suitable for satellite Field Of View (FOV) stated at the requirements of meteorological administration is determined and the precise satellite FOV and the size of distribution image is calculated on the basis of the image size of the determined observation area. The results in this paper were applied to the detailed design for COMS ground station and also are expected to be used for the future observation scheduling and the scheduling of distribution of user data.

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장주기파를 고려한 항만 가동율의 평가 (Evaluation of the Harbor Operation Rate Considering Long Period Waves)

  • 김규한
    • 한국해양공학회지
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    • 제16권2호
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    • pp.21-26
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    • 2002
  • In this study, the characteristics of long period waves are analyzed by field observation at Sokcho harbor on the eastern coast of Korea. firstly. the pressure data obtained from field observation are transformed into water surface elevations and the wave by wave analysis is applied to the observed wave data. also, we select long period waves by setting up the range 30-200sec, and suggest the relationship between ordinary waves and long period waves using the concept of the significant wave height. and, we examine the effects oft he long period waves on the rate of the harbor operation. The observation results demonstrate that the long period waves with heights of 1.2-14.6cm and periods of 35.8-162sec exist at Sokcho harbor. also, we found the rates of harbor operation based on long period waves are 61.8%-99.5% lower than the usual rates of 93.8%-100%.

현장학습을 위한 천체관측 프로그램의 개발과 적용 (Development and Application of Astronomical Observation Program for Field Trip)

  • 김상달;박종철
    • 대한지구과학교육학회지
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    • 제1권1호
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    • pp.52-62
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    • 2008
  • The purpose of this study is to find out learning content for astronomical observation that could perform astronomical programs regardless of weather conditions as a case for the present conditions of astronomical observation and the methods of new education for astronomical observation, and to suggest the methods of synchronized multiple astronomical observation and actual cases using the Internet network. The results are as follows. First, the method of galaxy-oriented astronomical education helped those attempting to approach astronomy academically for the first time grasp useful concepts as to the astronomical space, and let them look at the space in an objective sense, which was effective in forming cosmic structure and concepts. Second, the administration curriculum of astronomical observation team was related to data that systematically contained annual astronomical education concerning the operation of astronomical observation teams; thus, they could be suggested as beneficial teaching materials to the teachers who wanted to organize a school club meeting. Third, it has been noted that the level of students' satisfaction in p2d program and MSO program was very high, and they turned out to be effective learning methods that could be implemented even in times of rain when it would not be possible to conduct astronomical observation activities.

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한국형수치예보모델 자료동화에서 위성 복사자료 관측오차 진단 및 영향 평가 (Diagnostics of Observation Error of Satellite Radiance Data in Korean Integrated Model (KIM) Data Assimilation System)

  • 김혜영;강전호;권인혁
    • 대기
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    • 제32권4호
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    • pp.263-276
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    • 2022
  • The observation error of satellite radiation data that assimilated into the Korean Integrated Model (KIM) was diagnosed by applying the Hollingsworth and Lönnberg and Desrozier techniques commonly used. The magnitude and correlation of the observation error, and the degree of contribution for the satellite radiance data were calculated. The observation errors of the similar device, such as Advanced Technology Microwave Sounder (ATMS) and Advanced Microwave Sounding Unit-A shows different characteristics. The model resolution accounts for only 1% of the observation error, and seasonal variation is not significant factor, either. The observation error used in the KIM is amplified by 3-8 times compared to the diagnosed value or standard deviation of first-guess departures. The new inflation value was calculated based on the correlation between channels and the ratio of background error and observation error. As a result of performing the model sensitivity evaluation by applying the newly inflated observation error of ATMS, the error of temperature and water vapor analysis field were decreased. And temperature and water vapor forecast field have been significantly improved, so the accuracy of precipitation prediction has also been increased by 1.7% on average in Asia especially.

국가 기상기술력 수준 평가 - 한국, 미국, 일본을 대상으로 한 비교 연구 - (Capability Assessment on Meteorological Technology - Comparative Study of Technological Prowess on Korea, U.S., and Japan -)

  • 김세원;박길운;조창범;이영곤;임덕빈
    • 대기
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    • 제21권3호
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    • pp.319-336
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    • 2011
  • The objective of this study was to assess the meteorological capability of Korea by comparing with that of the U.S. and Japan as of 2010. The research was conducted based on various indices and surveys, and quantified the results using the Gordon's scoring model. The index assessment used 11 items derived from 9 segments - surface observation, advanced observation and observations quality in the observation field; data assimilation, numerical model and infrastructure in the data processing field; forecast accuracy in the forecast field; climate prediction and climate change in the climate field - in this research, we classified the meteorological technology into four fields. In the survey assessment, another 10 items in addition to the above 11 ones (total 21 items) were used. In the field of climate, Korea was found to lag far behind the U.S. (96.5p) and Japan (90.5p) with 77.6 points out of 100, which is 18.9 and 12.9 points lower than them respectively. On the other hand, Korea showed the narrowest gap with Japan (95.3p) and the U.S. (94.2) in the forecasting field, recording 90.3 points. Particularly, in surface observation, infrastructure and forecast accuracy segment, Korea was on a par with the U.S. and Japan, boasting 100.5 percent compared to their counterparts. However, in advanced observation, data quality and climate change segment, Korea was only at the level of 81.5 percent compared to that of the U.S. and Japan. All in all, the technological prowess of Korea, scoring 84.6 points, stood at 89.7 percent of that of the U.S. (94.3p) and 91.9 percent of Japan (92.1p).

파랑에 의한 해저지반의 액상화에 관한 현지관측과 해석 (Field Observation on Wave Induced Liquefaction in Sea-bed and its Analysis)

  • 이익효;선공기
    • 한국해안해양공학회지
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    • 제3권2호
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    • pp.100-107
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    • 1991
  • 본 연구는 실제의 해역에서 액상화 현상을 확인함과 동시에 필자 등이 제안하는 액상화 이론을 검증하는 것을 목적으로 한다. 본 연구의 내용 파랑에 의한 액상화에 대한 현지관측 및 이론해석의 두 부분으로 되어있다. 현지관측에서는 2년간에 걸쳐서 파고, 해저지반표면의 수압변동, 해저지반중의 변동간극수압 등을 관측하였으며, 이론해석에서는 필자 등이 제안하고 있는 액상화 이론에 근거하여 해석을 실시한 후 현지관측 자료와 비교하여 검토하였다.

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Information for Urban Risk Management: the Role of Remote and Close Sensing

  • Hofstee, Paul;Genderen, John van
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.162-164
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    • 2003
  • The multi-disciplinary research project Strengthening Local Authorities in Risk Management (SLARIM), initiated by ITC, includes three case study cities in Asia. An important question is: what are the essential data for risk management and how to access such data. The role of common sources (e.g. census data), data derived from remote sensing (high-resolution satellite imagery, aerial photos), and data from close sensing (field observation, including mobile GIS) to acquire essential risk management data will be discussed. Special attention is given to the question of the minimum area and to disaggregating population data. A few examples are given of Kathmandu / Lalitpur, Nepal.

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야외 지질학 탐구 요소 추출 및 지질 답사 교육 문헌 분석 (Drawing Elements of Inquiry in Field Geology and Analyzing Field Geology Education in Previous Studies)

  • 정찬미;신동희
    • 한국과학교육학회지
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    • 제37권3호
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    • pp.465-481
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    • 2017
  • 본 연구는 최근 20년간 국내외에서 수행된 야외 지질 답사 교육이 지질학 참 탐구의 특성을 어떻게 반영하고 있는지 분석한 문헌 분석 연구다. 이를 위해 먼저 야외 지질학자의 실제 연구 방법 및 과학 교육학적 중요성을 고려하여 야외 지질학 탐구 요소 다섯 가지(관찰, 표상, 귀추적 추론, 공간적 사고, 통시적 사고)를 도출하고, 이를 바탕으로 탐구 하위 요소를 추가하여 지질 답사 교육 분석 기준을 개발했다. 분석 대상 사례는 총 53건이었고, 분석은 야외 지질학 탐구 요소별 하위 요소 및 탐구 요소 전반이 나타나는 경향에 대해 수행되었다. 분석 결과, 관찰과 표상은 대부분의 사례에 포함되어 있었으며, 귀추적 추론, 공간적 사고, 통시적 사고 순으로 포함된 빈도수가 적었다. 관찰은 목적적 관찰 및 자유 관찰의 비율이 높았고, 표상에서는 시각화 언어화 유형과 자유 양식의 표상이 많이 나타났으며, 귀추적 추론에서는 가설 생성 단계가 포함되는 경우가 많고 가설 내용은 지질형성 과정과 관련된 경우가 많았다. 공간적 사고에서는 자기 위치화 및 공간 배치 형태 인식 유형이 높은 비율로 나타나고, 통시적 사고에서는 층서 유형의 사고가 가장 많이 나타났다. 3가지 이상의 야외 지질학 탐구 요소를 포함하는 경우는 전체 사례의 87%였다. 이 연구의 결과를 바탕으로 향후 참 과학 탐구로서 야외 지질 답사 교육의 활용과 관련한 시사점을 제시했다.