• Title/Summary/Keyword: Brightness Temperature

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Potential Effects of Land-Use Change on the Local climete (토지이용 변화가 국지기후에 미치는 영향)

  • 이현영
    • Korean Journal of Remote Sensing
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    • v.11 no.3
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    • pp.83-100
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    • 1995
  • The land-use has changed rapidly during the last two decades in accordance with urbanization in the Seoul Metropolitan Region. As a result of these changes, the local climate has undergone changes as well. This study intends to define the land-use changes, and then to show how they have brought in significant changes in the local climates. Land-use changes in the study area so repidly that up-to date maps and documents are not available at present. Therefore, Landsat data for land-use classification and NOAA AVHRR thermal data for the temperature fields were analyzed. Additionary, to visualize the effect of the land-use on the local climate, computer-enhanced brightness temperatures, Green Belt and city boundaries were overlaid on land-use patterns obtained from satellite images using GIS techniques. The results of analysis demonstrate that Green Space in the Seoul Metropolitan Region decreased from 94% to 62% while urban land-use increased ten times, from 4% to 39% for the period of 1972-1992. The resulting disappearance of biomass caused by land-use changes may have implications for the local-and micro-climate. The results show that the local climate of the study area became drier and warmer. This study also suggests a need for further studies of man's effects on local climate to minimize adverse influences and hazardous pollution and efficacious ways for urban planning.

Estimating Stability Indices from the MODIS Infrared Measurements over the Korean Peninsula (MODIS 적외 자료를 이용한 한반도 지역의 대기 안정도 지수 산출)

  • Park, Sung-Hee;Chung, Eui-Seok;Koenig, Marianne;Sohn, B.J.
    • Korean Journal of Remote Sensing
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    • v.22 no.6
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    • pp.469-483
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    • 2006
  • An algorithm was developed to estimate stability indices (SI) over the Korean peninsula using Terra Moderate Resolution Imaging Spectroradiometer (MODIS) infrared brightness temperatures (TBs). The SI is defined as the stability of the atmosphere in the hydrostatic equilibrium with respect to the vertical displacements and is used as an index for the potential severe storm development. Using atmosphere temperature and moisture profiles from Regional Data Assimilation and Prediction System (RDAPS) as initial guess data for a nonlinear physical relaxation method, K index (KI), KO Index (KO), lifted index (LI), and maximum buoyancy (MB) were estimated. A fast radiative transfer model, RTTOV-7, is utilized for reducing the computational burden related to the physical relaxation method. The estimated TBs from the radiative transfer simulation are in good agreement with observed MODIS TBs. To test usefulness for the short-term forecast of severe storms, the algorithm is applied to the rapidly developed convective storms. Compared with the SIs from the RDAPS forecasts and NASA products, the MODIS SI obtained in this research predicts the instability better over the pre-convection areas. Thus, it is expected that the nowcasting and short-term forecast can be improved by utilizing the algorithms developed in this study.

Quality Characteristics of Bokryung-Byung Prepared with Bokryung (Poria cocos Wolf) Powder (재료 배합비를 달리한 복령병의 품질특성)

  • Choi, Mi-Ae
    • Food Science and Preservation
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    • v.19 no.4
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    • pp.510-518
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    • 2012
  • In this research, to modernize traditional food and to make functional bokryung-byung, bokryung-byungwas made with Poriacocos Wolf powder added. During its storage, its moisture content ranged from 42.89 to 44.85%. The control group had the highes tmoisture content (44.85%), and it was reduced significantly as the Poriacocos Wolf powder in creased. The longer the storage period was, the lower the pH and the higher the acidity was. The total bacterial count increased from 2.70 to 3.00 Log CFU/g right after the manufacture and increased rapidly on the fourth day of the storage with more than 7.00 Log CFU/g. There was no difference between the control group and the bokryung-byung, though. The Hunter's color value after the manufacture, with the increase in the added Poriacocos Wolf powder, showed a significantly reduced brightness, but significantly increased redness and yellowness. Their chromaticity did not change, how ever, during their storageat a temperature of $20^{\circ}C$. The hardness, solidity, gumminess, and cohesiveness of the bokryung-byung increased, unlike in the control group, and its brittleness increased. In terms of the overall preference, the preference for the control group was high, but was higher when 5 % Poria cocos Wolf powder was added during the manufacture of the bokryung-byung. As a result of these correlations, it is believed that elastic and chewy dduks are preferred and bokryung-byungs could be developed as functional dduks.

Bias Characteristics Analysis of Himawari-8/AHI Clear Sky Radiance Using KMA NWP Global Model (기상청 전구 수치예보모델을 활용한 Himawari-8/AHI 청천복사휘도 편차 특성 분석)

  • Kim, Boram;Shin, Inchul;Chung, Chu-Yong;Cheong, Seonghoon
    • Korean Journal of Remote Sensing
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    • v.34 no.6_1
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    • pp.1101-1117
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    • 2018
  • The clear sky radiance (CSR) is one of the baseline products of the Himawari-8 which was launched on October, 2014. The CSR contributes to numerical weather prediction (NWP) accuracy through the data assimilation; especially water vapor channel CSR has good impact on the forecast in high level atmosphere. The focus of this study is the quality analysis of the CSR of the Himawari-8 geostationary satellite. We used the operational CSR (or clear sky brightness temperature) products in JMA (Japan Meteorological Agency) as observation data; for a background field, we employed the CSR simulated using the Radiative Transfer for TOVS (RTTOV) with the atmospheric state from the global model of KMA (Korea Meteorological Administration). We investigated data characteristics and analyzed observation minus background statistics of each channel with respect to regional and seasonal variability. Overall results for the analysis period showed that the water vapor channels (6.2, 6.9, and $7.3{\mu}m$) had a positive mean bias where as the window channels(10.4, 11.2, and $12.4{\mu}m$) had a negative mean bias. The magnitude of biases and Uncertainty result varied with the regional and the seasonal conditions, thus these should be taken into account when using CSR data. This study is helpful for the pre-processing of Himawari-8/Advanced Himawari Imager (AHI) CSR data assimilation. Furthermore, this study also can contribute to preparing for the utilization of products from the Geo-Kompsat-2A (GK-2A), which will be launched in 2018 by the National Meteorological Satellite Center (NMSC) of KMA.

A Study on Stability according to the Conservation Environment for Fixative of Korean Mural Painting Layers (한국 흙벽화 채색층 고착제의 보존환경에 따른 안정성 연구)

  • Jin, Byung-hyuk;Wi, Koang-chul
    • Korean Journal of Heritage: History & Science
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    • v.46 no.3
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    • pp.150-171
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    • 2013
  • The most important part of conservation treatment of murals is to preserve them against the risk of a damage by injecting fixative into them when the painting loses its cohesion or powderization of pigments occurred due to occurrence of cracks inside the painting layer. However, studies on the stability of fixative used for painting layers of murals are still insufficient. This study manufactured a mural as a specimen and colored it with four kinds of pigments including oyster shell white, cinnabar, malachite and red clay and applied four kinds of fixative, including, Paraloid $B-72^{(R)}$, Caparol-$binder^{(R)}$, glue and Hydoxypropyl $cellulose^{(R)}$. artificially generated environmental changes in temperature, humidity and ultraviolet rays which may occur after the completion of conservation treatment. Then the changes in physical properties were observed in multifaceted ways such as color stability, contact angle, brilliance, adhesive strength and surface. As a result, this study found that ultraviolet rays and hot?humid environment have a large impact on color stability causing changes in brightness and chroma of all painting layers where the fixative were applied, except for oyster shell white and are considered the main factors of decomposition by accelerating the aging process of fixatives applied. In comparison to the synthetic resins that were also tested in this study, the traditional glue showed satisfactory results in terms of color stability and influence preservation and the hydrophile property. As it showed exceptionally outstanding adhesive strength in all painting layers in the aspect of adhesive strength, it is considered to be highly stabile for the fixation treatment of painting layers of mural.

Predicting Unsaturated Soil Water Content Using CIELAB Color System-based Soil Color (CIELAB 색 표시계 기반 토색을 활용한 불포화토 함수비 예측 연구)

  • Baek, Sung-Ha;Park, Ka-Hyun;Jeon, Jun-Seo;Kwak, Tae-Young
    • Journal of the Korean Geotechnical Society
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    • v.39 no.2
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    • pp.31-42
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    • 2023
  • A study was conducted to use soil color obtained from digital im ages as an indicator of soil water content. Digital images of Jumoonjin standard sand with five different water contents were captured under nine different lighting conditions. Through digital image processing, the soil color of the sample was obtained based on the CIELAB color system, and the effect of lighting conditions and water content on the soil color was analyzed. The results indicated that L* showed a high correlation with illuminance, whereas a* and b* showed a high correlation with color temperature. As the water content increased, L*, which represents the brightness of the soil color, decreased, and a* and b* increased. Therefore, the soil color changed from green and blue to red and yellow. Based on the regression analysis results of lighting conditions, water content, and soil color, a water content predicting method based on the soil color of silica-based sand photographed under irregular light conditions was proposed. The proposed method can predict the water content with a m axim um error of 0.29%.

Statistical Analyses of Soil Moisture Data from Polarimetric Scanning Radiometer and In-situ (Polarimetric Scanning Radiometer 와 In-situ를 이용한 토양수분 자료의 통계분석)

  • Jang, Sun Woo;Jeon, Myeon Ho;Choi, Minha;Kim, Tae-Woong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.5B
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    • pp.487-495
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    • 2010
  • Soil moisture is a crucial factor in hydrological system which influences runoff, energy balance, evaporation, and atmosphere. United States National Aeronautic and Space Administration (NASA) and Department of Agriculture (USDA) have established Soil Moisture Experiment (SMEX) since 2002 for the global observations. SMEX provides useful data for the hydrological science including soil moisture and hydrometeorological variables. The purpose of this study is to investigate the relationship between remotely sensed soil moisture data from aircraft and satellite and ground based experiment. C-band of Polarimetric Scanning Radiometer (PSR) that observed the brightness temperature provides soil moisture data using a retrieval algorithm. It was compared with the In-situ data for 2-30 cm depth at four sites. The most significant depth is 2-10 cm from the correlation analysis. Most of the sites, two data are similar to the mean of data at 10 cm and the median at 7 cm and 10 cm at the 10% significant level using the Rank Sum test and t-test. In general, soil moisture data using the C-band of the PSR was established to fit the Normal, Log-normal and Gumbel distribution. Soil moisture data using the aircraft and satellites will be used in hydrological science as fundamental data. Especially, the C-band of PSR will be used to prove soil moisture at 7-10 cm depths.

The Influence of the Landscaping Shade Membrane's Brightness on the Mean Radiant Temperature(MRT) of Summer Outdoor (조경용 차양막 재료의 명도가 하절기 옥외공간의 평균복사온도에 미치는 영향)

  • Lee, Chun-Seok;Ryu, Nam-Hyung
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.5
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    • pp.65-73
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    • 2015
  • The purpose of this study was to compare the Mean Radiant Temperature(MRT) under two landscaping shade membranes, white and black, with those of natural outdoor spaces at summer midday. An additional perforated black shading net was applied and compared for the consideration of the practical application. The average MRT at the height of 2.4m, 10cm below the membranes of black, white, and perforated black were $49.1^{\circ}C$, $41.6^{\circ}C$ and $36.8^{\circ}C$ respectively, while that of open sky was $41.8^{\circ}C$. This indicates that a closer position to the darker membrane caused a higher MRT. At the height of 1.1m and 1.7m, the difference of MRT between the black and the white membranes was slight, while the value of white was unexpectedly higher than the black. The MRT of black perforated net showed the lowest value at every height. The black membrane absorbed more solar radiation than the white, which caused the greater release of long wave radiation and higher temperature near the membrane itself. In spite of the higher albedo of the white membrane, the higher solar radiation transmittance rate of which seemed to cause the slightly higher MRT than the black at the hight of 1.1m and 1.7m. In summary, the performance of the black membrane was slightly better than the white in terms of the air conditioning of the human related space around the height of 1.1m and 1.7m, when the shading membranes were at 2.5m height.

Monitoring of Quality Characteristics of Danmooji Product Storage Temperatures for Storage Temperature Establishment (단무지 제품의 보관온도 설정을 위한 저장 온도별 품질 특성)

  • Jung, Hyeon A;Park, Chan Sung;Park, Suk Hyeon
    • Food Science and Preservation
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    • v.19 no.6
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    • pp.818-824
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    • 2012
  • In this study, danmuji samples stored at 5 and $25^{\circ}C$ were examined for three weeks to observe the changes in the color, property of matter, and microorganisms of danmuji, and its sensory properties, during its storage. The difference in the brightness and redness of danmuji and danmuji filtrate as their storage period became longer was not big but was significant, and their yellowness decreased following storage at both 5 and $25^{\circ}C$. The hardness of the danmuji sample stored at $5^{\circ}C$ showed the greatest value at day 7 while that of the danmuji sample stored at $25^{\circ}C$ showed the greatest value at day 14. It was found in the examination of the total cell number of the stored danmuji that the total cell number was $10^5CFU/g$, with almost no change, but in the case of the danmuji filtrate, the cell number increased from the latter part of the storage. The number of yeast fungi increased until storage day 7 for both the danmuji sample stored at $5^{\circ}C$ and that stored at $25^{\circ}C$. The cell number of danmuji did not change since then while the cell number of the danmuji filtrate constantly increased. As for the sensory properties of each stored danmuji, the overall taste preference was highest at storage days 14 and 21 ($5^{\circ}C$), and the overall scent preference was high for the danmuji that had been stored for 7 days ($5^{\circ}C$), but there was no significant difference. The texture and color of and the overall preference for the danmuji stored at $25^{\circ}C$ significantly decreased as the storage period got longer. All in all, the preference for the danmuji stored at $5^{\circ}C$ was higher than that for the danmuji stored at $25^{\circ}C$, although there was no significant difference. Thus, it is thought that $5^{\circ}C$ is more appropriate than $25^{\circ}C$ as the storage temperature of danmuji products.

Quality Characteristics of Frozen Doraji (Platycodon grandiflorum) according to Various Blanching Treatment Conditions (블랜칭 처리 조건에 따른 동결 도라지의 품질 특성)

  • Lee, Young-Joo;Lee, Hye-Ok;Kim, Ji-Young;Kwon, Ki-Hyun;Cha, Hwan-Soo;Kim, Byeong-Sam
    • Food Science and Preservation
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    • v.18 no.5
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    • pp.661-668
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    • 2011
  • This study was conducted to devise appropriate blanching-process conditions as a means to convert Doraji, which is widely used in Korean food due to its unique fragrance and flavor, into frozen food materials for various uses. For the Hunter L values representing the brightness transformation among the surface color and gloss changes that were observed in Doraji before and after freezing, and after Doraji went through a blanching process, the specimen that went through a blanching process at $80^{\circ}C$ showed a significantly higher value compared to another specimen processed at a higher temperature, and the first specimen's value also rose after freezing. Meanwhile, for the hardness values, they declined more as the blanching temperature became higher and as the processing time became longer. For the number of total counts and the number of coliform groups, the number of total counts at $3.75{\times}10^5$ and $1.25{\times}10^5$ cfu/g before the blanching process was reduced into the approximately 2-3 log scale, and no coliform group was detected after the blanching process. As for the peroxidase activity, its activation was decreased by the blanching process, and more than 89% of the peroxidase became inactivated in all the specimens that went through the blanching process. The sensory characteristics of the frozen-thawed Doraji by test group showed the radish leaves blanched at $90^{\circ}C$ for 1 min to be the most highly evaluated in terms of the overall preference level (p<0.05).