• Title/Summary/Keyword: observation environment

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The Analysis of GOCI CDOM for Observation of Ocean Environment Change (해양환경변화관측을 위한 GOCI CDOM 자료 분석)

  • Jeong, Jong-Chul
    • Journal of Environmental Impact Assessment
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    • v.22 no.4
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    • pp.389-395
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    • 2013
  • Geostationary Ocean Color Imager(GOCI), the World's first spaceborne ocean color observation satellite operated in geostationary orbit, was successfully launched on May 2010. The main missions of GOCI is the coastal environment monitoring of GOCI in order to meet the necessity of long-term climate change monitoring and research. The GOCI have higher spatial resolution than MODIS, $500m{\times}500m$, and 8 spectral ocean color channels. GOCI have a capability for observation on the coastal environment change, GOCI perform the observation with 8 times a day. In this paper, we presented the more improved results for observation on the coastal environment change than MODIS ocean color sensor and detected the spatial difference of CDOM for monitoring coastal environment change.

STATISTICAL ANALYSIS OF BOAO OBSERVATION ENVIRONMENT: 1998~2004 (보현산천문대의 관측환경 통계 분석 : 1998년~2004년)

  • PARK YOON-HO;PARK BYEONG-GON;ANN HONG-BAE
    • Publications of The Korean Astronomical Society
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    • v.19 no.1
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    • pp.55-63
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    • 2004
  • Observation environment of the Bohyunsan Optical Astronomy Observatory(BOAO) has been examined using various statistical data including real observation times versus allocated times and seeing statistics. The data have been collected from the observation logs of the 1.8m telescope in the period 1998 - 2004. New criteria have been set up to calculate a more realistic observation efficiency of the observatory. The new statistical analysis based on the new criteria gives the overall observation efficiency of BOAO as $38.6\%$, that is equivalent to 115.8 observable nights out of 300 allocatable nights. The seeing statistics shows that the mean seeing measured at the focal images is 2".3. The present study of the observation environment of BOAO suggests that differential photometry and spectroscopy should be preferred modes of observation to maximize the productivity of BOAO.

Characteristics of Ozone Advection in Vertical Observation Analysis Around Complex Coastal Area (연직관측자료를 통한 복잡 연안지역의 오존 이류특성)

  • Lee, Hwa-Woon;Park, Soon-Young;Lee, Soon-Hwan;Leem, Heon-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.25 no.1
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    • pp.57-74
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    • 2009
  • In order to clarify the vertical ozone distribution in planetary boundary layer of coastal area with complex terrain, an observation campaign was carried out around Gwangyang Bay with dense pollutant emission sources during two days from June, 4 2007. For this observation are Radiosonde, SODAR(SOnic Detection And Ranging) and Tethered ozone sonde were employed. The surface meteorological and photochemical observation data provided by AWS (Automatic Weather System) and AQMS (Air Quality Monitoring System) were also applied for analysis. Synoptic condition is strongly associated with lower level ozone distribution in complex terrain coastal area. Since mesoscale circulation induced by difference of characteristics of land and sea and orographic forcing is predominant under calm synoptic condition, vertical distribution of ozone is complicate and vertical ozone concentration greatly fluctuated. However in second day when synoptic influence become strong, ozone concentration in lower levels is vertically uniform regardless of observation level. This results in vertical observation indicates that vertical ozone distribution is often determined by synoptic condition and also affects surface ozone concentration.

Assessment of Observation Environment for Surface Wind in Urban Areas Using a CFD model (CFD 모델을 이용한 도시지역 지상바람 관측환경 평가)

  • Yang, Ho-Jin;Kim, Jae-Jin
    • Atmosphere
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    • v.25 no.3
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    • pp.449-459
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    • 2015
  • Effects of buildings and topography on observation environment of surface wind in central regions of urban areas are investigated using a computational fluid dynamics (CFD) model. In order to reflect the characteristics of buildings and topography in urban areas, geographic information system (GIS) data are used to construct surface boundary input data. For each observation station, 16 cases with different inflow directions are considered to evaluate effects of buildings and topography on wind speed and direction around the observation station. The results show that flow patterns are very complicated due to the buildings and topography. The simulated wind speed and direction at the location of each observation station are compared with those of inflow. As a whole, wind speed at observation stations decreases due to the drag effect of buildings. The decrease rate of wind speed is strongly related with total volume of buildings which are located in the upwind direction. It is concluded that the CFD model is a very useful tool to evaluate location of observation station suitability. And it is expected to help produce wind observation data that represent local scale excluding the effects of buildings and topography in urban areas.

A Case Study on Rainfall Observation and Intensity Estimation using W-band FMCW Radar (W밴드 FMCW 레이더를 이용한 강우 관측 및 강우 강도 추정 사례 연구)

  • Jang, Bong-Joo;Lim, Sanghun
    • Journal of Korea Multimedia Society
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    • v.22 no.12
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    • pp.1430-1437
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    • 2019
  • In this paper, we proposed a methodology for estimating rainfall intensity using a W-band FMCW automotive radar signal which is the core technology of autonomous driving car. By comparing and analyzing the results of rainfall and non-rainfall observation, we found that the reflection intensity of the automotive radar is changed with rainfall intensity. We could confirm the possibility of deriving the quantitative precipitation estimation using the methodology derived from this result. In addition it can be possible to develop a new paradigm of precipitation observation technique by observing various events together with the weather radar and the ground rainfall observation equipment.

Assessment of Observation Environments of Automated Synoptic Observing Systems Using GIS and WMO Meteorological Observation Guidelines (GIS와 WMO 기상 관측 환경 기준을 이용한 종관기상관측소 관측환경평가)

  • Kang, Jung-Eun;Kim, Jae-Jin
    • Korean Journal of Remote Sensing
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    • v.36 no.5_1
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    • pp.693-706
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    • 2020
  • For ten meteorological observatories running an automated synoptic observing system (ASOS), we classified the observation environments into five classes based on the World Meteorological Organization (WMO) classification guidelines. Obstacles (such as topography and buildings) and land-cover types were the main factors in evaluating the observation environments for the sunshine duration, air-temperature, and surface wind. We used the digital maps of topography, buildings, and land-cover types. The observation environment of the sunshine duration was most affected by the surrounding buildings when the solar altitude angle was low around the sunrise and sunset. The air-temperature observation environment was determined based on not only the solar altitude angle but the distance between the heat/water source and ASOS. There was no water source around the ASOSs considered in this study. Heat sources located near some ASOSs were not large enough to affect the observation environment. We evaluated the surface wind observation environment based on the roughness length around the ASOS and the distance between surrounding buildings and the ASOS. Most ASOSs lay at a higher altitude than the surroundings and the roughness lengths around the ASOSs were small enough to satisfy the condition for the best level.

A Study on the Spatial Planning and the Characteristics of User's Need in the Children's Library (어린이도서관에 있어서 이용자요구특성과 공간구성에 관한 연구)

  • Lee, Jeong-Mi;Kwack, Dong-Wha;Lim, Che-Zinn
    • Korean Institute of Interior Design Journal
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    • v.16 no.6
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    • pp.213-223
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    • 2007
  • This study investigates the mutual effects of the physical environment and the characteristics of user's need in the children's libraries of open plan type. The children's library as a flexible space should accept user's diverse needs. Especially, Children express more positive and diverse behaviors than adults in physical environment. As the design information obtained from observation of children's behaviors are put to architectural design, the more affluent environment in which children can do positive behaviors can be made. We used two research methods of the behavior observation and interview for the children's library, and could formulate various using actions through the behavior setting observation for using library. A relational description for reading environment in this study, based on the affordance and the behavior setting theories, provided us with rich accounts for the psychological and sociocultural resources in the children's library. Consequently, the following results can be summarized. First, children need territories for family use and for place and are using library effectively through taking the two territories. Second, the zoning according to age category should be done, as behavior patterns were observed differently according to age. Third, the space composition with openness should be designed, as children need social relation and learning through imitation and observation.

Visibility Estimated from the Multi-wavelength Sunphotometer during the Winter 2011 Intensive Observation Period at Seoul, Korea (2011년 겨울철 서울시 대기 집중 관측 기간 동안 다파장 복사계로 분석된 에어러솔 연직분포와 시정 거리)

  • Lee, Kwon-Ho;Kim, Kyung-Won;Kim, Gwanchul;Jung, Kweon;Lee, Soon-Hee
    • Journal of Korean Society for Atmospheric Environment
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    • v.29 no.5
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    • pp.682-691
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    • 2013
  • The aerosol extinction vertical profile and surface visibility have been derived from the Microtops-II sunphotometer observation during the winter 2011 intensive observation period (IOP) at Seoul, Korea. Using models of degradation of aerosol optical thickness (AOT) and aerosol scale height, we have performed extinction-visibility modulation to determine the height dependent aerosol extinction and visibility. It is shown that the aerosol loading is relatively low during IOP (mean $AOT_{550}=0.22{\pm}0.08$, ${\AA}$ngstr$\ddot{o}$m exponent=$1.14{\pm}0.26$). Modeled extinction by use of Microtops II sunphotometer data shows good agreement with measurements by the Multi-wavelenth Polarization Lidar (MPoLAR), and the derived surface visibility are consistent with data from the transmissometer. These results emphasize the use of a vertically resolved extinction from AOT to predict visibility conditions at ground level.

Analysis of Multi-Differential GNSS Positioning Accuracy in Various Signal Reception Environments

  • Tae, Hyunu;Kim, Hye-In;Park, Kwan-Dong
    • Journal of Positioning, Navigation, and Timing
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    • v.7 no.1
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    • pp.15-24
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    • 2018
  • This study analyzed positioning accuracy of the multi-differential global navigation satellite system (DGNSS) algorithm that integrated GPS, GLONASS, and BDS. Prior to the analysis, four sites of which satellite observation environment was different were selected, and satellite observation environments for each site were analyzed. The analysis results of the algorithm performance at each of the survey points showed that high positioning performance was obtained by using DGPS only without integration of satellite navigation systems in the open sky environment but the positioning performance of multi-DGNSS became higher as the satellite observation environments degraded. The comparison results of improved positioning performance of the multi-DGNSS at the poor reception environment compared to differential global positioning system (DGPS) positioning results showed that horizontal accuracy was improved by 78% and vertical accuracy was improved by 65% approximately.