• Title/Summary/Keyword: Split Window

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An Analysis of Variance Procedure for the Split-Plot Design Using SPSS Syntax Window

  • Choi Byoung-Chul
    • Communications for Statistical Applications and Methods
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    • v.12 no.1
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    • pp.61-69
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    • 2005
  • In conducting the analysis of variance for the split-plot design using the statistical package SPSS, users including statisticians are faced with difficulties because of no appropriate example in the SPSS applications guide book. In this paper, therefore, we present an analysis of variance procedure for the split-plot design using SPSS syntax window.

Estimation of Total Precipitable Water from MODIS Infrared Measurements over East Asia (MODIS 적외 자료를 이용한 동아시아 지역의 총가강수량 산출)

  • Park, Ho-Sun;Sohn, Byung-Ju;Chung, Eui-Seok
    • Korean Journal of Remote Sensing
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    • v.24 no.4
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    • pp.309-324
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    • 2008
  • In this study the retrieval algorithms have been developed to retrieve total precipitable water (TPW) from Terra/Aqua Moderate Resolution Imaging Spectroradiometer (MODIS) infrared measurements using a physical iterative retrieval method and a split-window technique over East Asia. Retrieved results from these algorithms were validated against Defense Meteorological Satellite Program (DMSP) Special Sensor Microwave/Imager (SSM/I) over ocean and radiosonde observation over land and were analyzed for investigating the key factors affecting the accuracy of results and physical processes of retrieval methods. Atmospheric profiles from Regional Data Assimilation and Prediction System (RDAPS), which produces analysis and prediction field of atmospheric variables over East Asia, were used as first-guess profiles for the physical retrieval algorithm. We used RTTOV-7 radiative transfer model to calculate the upwelling radiance at the top of the atmosphere. For the split-window technique, regression coefficients were obtained by relating the calculated brightness temperature to the paired radiosonde-estimated TPW. Physically retrieved TPWs were validated against SSM/I and radiosonde observations for 14 cases in August and December 2004 and results showed that the physical method improves the accuracy of TPW with smaller bias in comparison to TPWs of RDAPS data, MODIS products, and TPWs from split-window technique. Although physical iterative retrieval can reduce the bias of first-guess profiles and bring in more accurate TPWs, the retrieved results show the dependency upon initial guess fields. It is thought that the dependency is due to the fact that the water vapor absorption channels used in this study may not reflect moisture features in particular near surface.

Analysis of Cloud Types and Low-Level Water Vapor Using Infrared Split-Window Data of NOAA/AVHRR (NOAA/AVHRR 적외 SPLIT WINDOW 자료를 이용한 운형과 하층수증기 분석)

  • 이미선;이희훈;서애숙
    • Korean Journal of Remote Sensing
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    • v.11 no.1
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    • pp.31-45
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    • 1995
  • The values of brightness temperature difference (BTD) between 11um and 12um infrared channels may reflect amounts of low-level water vapor and cloud types due to the different absorptivity for water vapor between two channels. A simple method of classifying cloud types at night was proposed. Two-dimensional histograms of brightness temperature of the 11um channel and the BTD between the split window data over subareas around characteristic clouds such as Cb(cumulonimbus), Ci(cirrus), and Sc(stratocumulus) was constructed. Cb, Ci and Sc can be classified by seleting appropriate thresholds in the two-dimensional histograms. And we can see amounts of low-level water vapor in clear area as well as cloud types in cloudy area in the BTD image. The map of cloud types and low-level water vapor generated by this method was compared with 850hPa and 1000hPa relative humidity(%) of numerical analysis data and nephanalysis chart. The comparisons showed reasonable agreement.

Aesthetics and Meaning of Split Screen: Focusing on Feature Film (화면 분할의 미학과 의미 - 극영화를 중심으로)

  • Chang, Woo-Jin
    • The Journal of the Korea Contents Association
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    • v.12 no.1
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    • pp.154-165
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    • 2012
  • In this paper, I examine the history of split screens, primarily seek to explain types of them, and explore the narrative meaning of each type in feature films. In short, I try to categorize the types of split screens and present a figure of them according to events and characters, focusing the relations between/among simultaneous images and narrative meanings. In addition, I assert that split screen have altered some methods of filmic storytelling and the ontology of screen. Story lines no longer have to be linear and the screen need not to remain a window through which we can see another world. The screen has come to be a canvas upon which several images can be arranged for narrative purposes.

A Study on Comparison of Satellite-Tracked Drifter Temperature with Satellite-Derived Sea Surface Temperature of NOAA/NESDIS

  • Park, Kyung-Ae;Chung, Joug-Yul;Kim, Kuh;Choi, Byung-Ho
    • Korean Journal of Remote Sensing
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    • v.10 no.2
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    • pp.83-107
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    • 1994
  • Sea surface temperatures (SSTs) estimated by using the operational SST derivation equations of NOAA/NESDIS were compared with satellite-tracked drifter temperatures. As a result of eliminating cloud-filled or contaminated pixels through several cloud tests, 69 matchup points between the drifter temperatures and the SSTs estimated with NOAA satellite 9, 10. 11 and 12 data from August, 1993 to July, 1994 were collected. Multi-channel sea surface temperature(MCSST) using a split window technique showed an approximately $1.0{\circ}C$ rms error as compared with the drifting buoy temperatures for 69 coincidences. Accuracies for satellete-derived sea surface temperatures were evaluated for only NOAA-11 AVHRR data which had relatively large matchups of 35points as compared with other satellites. For the comparison of the oberved temperatures with the calculated SSTs, linear MCSST and nonlinear cross product sea surface temperature(CPSST) algorithms by the split, the dual and the triple window technique were used respectively. As a result, the split window CPSSTs showed the smallest rms error of $0.72{\circ}C$. Defferences between the split window SSTs and the drifter temperatures appeared th have a linear tendency against the drifter temperatures and also against the differences between AVHRR channel 4 and 5 brighness temperatures. This indicates some possibilities that satelite-derived SSTs operationally calculated from the NOAA/NESDIS equation in the seas around Korea have been underestimated as compared with actural SSTs in case sea water temperature is relatively low or the atmosphere over the sea surface is very dry like in winter, while overstimated in case of high temperature or very moist atmospheric equations based on local sea measurements around Korea instead of global measurements should be derived.

COMPARISON OF ATMOSPHERIC CORRECTION ALGORITHMS FOR DERIVING SEA SURFACE TEMPERATURE AROUND THE KOREAN SEA AREA USING NOAA/AVHRR DATA

  • Yoon, Suk;Ahn, Yu-Hwan;Ryu, Joo-Hyung;Won, Joong-Sun
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.518-521
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    • 2007
  • To retrieve Sea Surface Temperature(SST) from NOAA-AVHRR imagery the spilt window atmospheric correction algorithm is generally used. Recently, there have been various new algorithms developed to process these data, namely the variable-coefficient split-window, the R54 transmittance-ratio method, fixed-coefficient nonlinear algorithm, dynamic water vapour (DWV) correction method, Dynamic Water Vapour and Temperature algorithm (DWVT). We used MCSST (Multi-Channel Sea surface temperature) and NLSST(Non linear sea surface temperature) algorithms in this study. The study area is around the Korea sea area (Yellow Sea). We compared and analyzed with various methods by applying each Ocean in-situ data and satellite data. The primary aim of study is to verify and optimize algorithms. Finally, this study proposes an optimized algorithm for SST retrieval.

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Estimation of Precipitable Water from the GMS-5 Split Window Data (GMS-5 Split Window 자료를 이용한 가강수량 산출)

  • 손승희;정효상;김금란;이정환
    • Korean Journal of Remote Sensing
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    • v.14 no.1
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    • pp.53-68
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    • 1998
  • Observation of hydrometeors' behavior in the atmosphere is important to understand weather and climate. By conventional observations, we can get the distribution of water vapor at limited number of points on the earth. In this study, the precipitable water has been estimated from the split window channel data on GMS-5 based upon the technique developed by Chesters et al.(1983). To retrieve the precipitable water, water vapor absorption parameter depending on filter function of sensor has been derived using the regression analysis between the split window channel data and the radiosonde data observed at Osan, Pohang, Kwangiu and Cheju staions for 4 months. The air temperature of 700 hPa from the Global Spectral Model of Korea Meteorological Administration (GSM/KMA) has been used as mean air temperature for single layer radiation model. The retrieved precipitable water for the period from August 1996 through December 1996 are compared to radiosonde data. It is shown that the root mean square differences between radiosonde observations and the GMS-5 retrievals range from 0.65 g/$cm^2$ to 1.09 g/$cm^2$ with correlation coefficient of 0.46 on hourly basis. The monthly distribution of precipitable water from GMS-5 shows almost good representation in large scale. Precipitable water is produced 4 times a day at Korea Meteorological Administration in the form of grid point data with 0.5 degree lat./lon. resolution. The data can be used in the objective analysis for numerical weather prediction and to increase the accuracy of humidity analysis especially under clear sky condition. And also, the data is a useful complement to existing data set for climatological research. But it is necessary to get higher correlation between radiosonde observations and the GMS-5 retrievals for operational applications.

Retrieval of emissivity and land surface temperature from MODIS

  • Suh Myoung-Seok;Kang Jeon-Ho;Kim So-Hee;Kwak Chong-Heum
    • Proceedings of the KSRS Conference
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    • 2005.10a
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    • pp.165-168
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    • 2005
  • In this study, emissivity and land surface temperature (LST) were retrieved using the previously developed algorithms and Aqua/MODIS data. And sensitivity of estimated emissivity and LST to the predefined values, such as land cover, normalized difference vegetation index (NOVI) and spectral emissivity were investigated. The methods used for emissivity and LST were vegetation cover method (VCM) and four different split-window algorithms. The spectral emissivity retrieved by VCM was not sensitive to the NOVI error but more sensitive to the land cover error. The comparison of LST showed that the LST was systematically different without regard to the land cover and season. And the LST was very sensitive to the emissivity error excepting the Uliveri et al. This preliminary result indicates that more works are needed for the retrieval of reliable LST from satellite data.

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Application of the Daylight Factor Formula with the Modified Split Flux (Modified Split Flux를 이용한 주광률 계산식 적용에 관한 연구)

  • Yun, Su-In;Yun, Gyeong;Kim, Kang-Soo
    • Journal of the Korean Solar Energy Society
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    • v.34 no.6
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    • pp.39-47
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    • 2014
  • Daylighting has a great effect on people inside the room. It is also closely related to the lighting energy consumption. Daylight factor(DF) is a very important index for evaluation of the daylighting in overcast sky. The objective of this study is to verify the suitability of the Tregenza's Modified Split Flux formula for the calculation of the daylight factor. We compared the daylight factors calculated by two methods; one by a measurement with 1/5 scale model and the other by the Daysim program. We used variables for verification as window wall ratios(WWR) and angles of the sky visible. As a result, daylight factor calculated by Modified Split Flux is similar to the measurement when more daylight enters the inside. And error is significantly increased when the angle of the sky visible is $50^{\circ}$.