• Title/Summary/Keyword: Brightness

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Assessment of the Relationship between Air Temperature and TOA Brightness Temperature in Different Seasons Using Landsat-8 TIRS (Landsat-8 위성의 열적외 센서를 활용한 대기온도와 밝기온도의 계절별 상관관계 분석)

  • CHOUNG, Yun-Jae;CHUNG, Youn-In;CHOI, Soo-Young
    • Journal of the Korean Association of Geographic Information Studies
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    • v.21 no.2
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    • pp.68-79
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    • 2018
  • In general, Top Of Atmosphere(TOA) brightness temperature is closely related to air temperature. Brightness temperature can be derived from the Thermal Infra-Red Sensors (TIRS) of the earth observation satellites such as the Landsat series. The TIRS instrument of the Landsat-8 satellite collects the two spectral bands (Bands 10 and 11) that measure brightness temperature. In this research, the relationship between the air temperature data measured by the weather stations in Seoul, South Korea and the brightness temperature data separately derived from Bands 10 and 11 of the Landsat-8 satellite were assessed in the different seasons through the correlation analysis. The statistical results led to the following conclusions. First, brightness temperature is closely related to air temperature in order of Spring, Autumn, Winter and Summer. Second, when air temperature increases, brightness temperature also increases in Spring, Autumn and Winter but decreases in Summer. Third, Band 10 has a closer relationship to air temperature than Band 11.

Brightness Value Comparison Between KOMPSAT-2 Images with IKONOS/GEOEYE-1 Images (KOMPSAT-2 영상과 IKONOS/GEOEYE-1 영상의 밝기값 상호비교)

  • Kim, Hye-On;Kim, Tae-Jung;Lee, Hyuk
    • Korean Journal of Remote Sensing
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    • v.28 no.2
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    • pp.181-189
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    • 2012
  • Recently, interest in potential for estimating water quality using high resolution satellite images is increasing. However, low SNR(Signal to Noise Ratio) over inland water and radiometric errors such as non-linearity of brightness value of high resolution satellite images often lead to accuracy degradation in water quality estimation. Therefore radiometric correction should be carried out to estimate water quality for high resolution satellite images. For KOMPSAT-2 images parameters for brightness value-radiance conversion are not available and precise radiometric correction is difficult. To exploit KOMPSAT-2 images for water quality monitoring, it is necessary to investigate non-linearity of brightness value and noise over inland water. In this paper, we performed brightness value comparison between KOMPSAT-2 images and IKONOS/GeoEye-1, which are known to show the linearity. We used the images obtained over the same area and on the same date for comparison. As a result, we showed that although KOMPSAT-2 images are more noisy;the trend of brightness value and pattern of noise are almost similar to reference images. The results showed that appropriate target area to minimize the impact of noise was $5{\times}5$. Non-linearity of brightness value between KOMPSAT-2 and reference images was not observed. Therefore we could conclude that KOMPSAT-2 may be used for estimation of water quality parameters such as concentration of chlorophyll.

A Study on Possibility of Improvement of MIR Brightness Temperature Bias Error of KOMPSAT-3A Using GEOKOMPSAT-2A (천리안2A호를 이용한 다목적실용위성3A호 중적외선 밝기 온도 편향오차 개선 가능성 연구)

  • Kim, HeeSeob
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.48 no.12
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    • pp.977-985
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    • 2020
  • KOMPSAT-3A launched in 2015 provides Middle InfraRed(MIR) images with 3.3~5.2㎛. Though the satellite provide high resolution images for estimating bright temperature of ground objects, it is different from existing satellites developed for natural science purposes. An atmospheric compensation process is essential in order to estimate the surface brightness temperature from a single channel MIR image of KOMPSAT-3A. However, even after the atmospheric compensation process, there is a brightness temperature error due to various factors. In this paper, we analyzed the cause of the brightness temperature estimation error by tracking signal flow from camera physical characteristics to image processing. Also, we study on possibility of improvement of MIR brightness temperature bias error of KOMPSAT-3A using GEOKOMPSAT-2A. After bias compensation of a real nighttime image with a large bias error, it was confirmed that the surface brightness temperature of KOMPSAT-3A and GEOKOMPSAT-2A have correlation. We expect that the GEOKOMPSAT-2A images will be helpful to improve MIR brightness temperature bias error of KOMPSAT-3A.

A Light Pipe Based Recycling Scheme for LED Brightness Enhancement

  • Ouyang, George;Li, Kenneth
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1149-1151
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    • 2007
  • As a follow-up to our previous work we present in this paper some experimental results on LED light recycling. Specifically we demonstrate for the first time that screen brightness can be increased using our light pipe based light recycling scheme for reallife projection display applications.

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Increased LED Brightness for Projection Displays - Compact to High Output Systems

  • Li, Kenneth
    • 한국정보디스플레이학회:학술대회논문집
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    • 2008.10a
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    • pp.1433-1434
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    • 2008
  • LED has gained its importance in the projection display market from very compact, micro-projectors to potentially high output, desktop systems. In both of these systems, the output levels are less than desirable. This paper describes practical recycling and multiplexing systems that provide brightness increases, and allow projectors to achieve outputs beyond its current levels.

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A Study on Takenical Development that by BLU Part (BLU 부품 기술개발 연구)

  • Kim, Soo-Yong;Lee, Oh-Keol
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1804-1807
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    • 2001
  • By comparing and analyzing the feature, brightness, chromaticity and uniformity of domestic LGPs and Japanese products, early home-manufacturing and stabilization in home-manufacturing are possible. By comparing and analyzing the distribution of brightness as sheets are varied, we can design an ideal sheet composition.

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Image Analysis of Diffuse Liver Disease using Computer-Adided Diagnosis in the Liver US Image (간 초음파영상에서 컴퓨터보조진단을 이용한 미만성 간질환의 영상분석)

  • Lee, Jinsoo;Kim, Changsoo
    • Journal of the Korean Society of Radiology
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    • v.9 no.4
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    • pp.227-234
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    • 2015
  • In this paper, we studied possibility about application for CAD on diffuse liver disease through pixel texture analysis parameters(average gray level, skewness, entropy) which based statistical property brightness histogram and image analysis using brightness difference liver and kidney parenchyma. The experiment was set by ROI ($50{\times}50$ pixels) on liver ultrasound images.(non specific, fatty liver, liver cirrhosis) then, evaluated disease recognition rates using 4 types pixel texture analysis parameters and brightness gap liver and kidney parenchyma. As a results, disease recognition rates which contained average brightness, skewness, uniformity, entropy was scored 100%~96%, they were high. In brightness gap between liver and kidney parenchyma, non specific was $-1.129{\pm}12.410$ fatty liver was $33.182{\pm}11.826$, these were shown significantly difference, but liver cirrhosis was $-1.668{\pm}10.081$, that was somewhat small difference with non specific case. Consequently, pixel texture analysis parameter which scored high disease recognition rates and CAD which used brightness difference of parenchyma are very useful for detecting diffuse liver disease as well as these are possible to use clinical technique and minimize reading miss. Also, it helps to suggest correct diagnose and treatment.

Research Representative Color Image Emotion Emotional Image Size Changes through Tree (영상 이미지 색채 감성트리를 통한 대표감성크기 변화 연구)

  • Lee, Yean-Ran;Park, Hyo-Jin
    • The Journal of the Korea Contents Association
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    • v.15 no.11
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    • pp.10-17
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    • 2015
  • Emotional computer that you want to study in a regular number change is the continuing sensitivity. Emotional Computing manner the sensibilities numbered and emotions were running through the trees. Emotional assessment of emotional sensibility computing was used as the coordinates of the key effects of the James A. Russell (Core Affect). Emotional tree runs purpose was to verify the correlation of sensitivity and emotion computing tree. Emotional tree attributes experiment color, brightness, saturation was configured with. When 50% brightness increase, about pleasure (X-axis) has increased by 10.49 points. Brightness 50%, GREEN 50% increase in the degree of pleasure (X-axis) of 10.49 points, tone (Y axis) has increased by 15.85 points. Brightness 50%, GREEN 50% increase in the degree of pleasure (X-axis) of 10.49 points, tone (Y axis) has increased by 15.85 points. Brightness 50% of the free-extent (X-axis), BLUE 50% when the tone (Y axis), pleasure extent (X-axis) of 10.49 points, tone (Y axis) as much as 14.65 points sensibilities have changed. When representatives emotions size changes have increased 50% brightness, color RED 50%, increased 5.4% Emotional excitement, emotion depressed declined -4.2%. 50% brightness, color GREEN 50% increase in emotional excitement had increased to 8.6%, declined by -5.5% this melancholy sensibility. Representative emotion and emotional changes increase or decrease the size of the emotional attributes were analyzed by quantitative methods. After the happy emotions number is needed to study more similar to the human emotion through the execution of the video image emotion emotional tree computing.

Comparison Between Face Color Change and Its Recognition Difference on Asian: Korean, Indonesian and Vietnamian (아시아인의 얼굴색 변화와 인지도간 상관성 비교 : 한국인, 인도네시아인, 베트남인)

  • Jung, Yu Chul;Lee, Meoung Ryul;Kim, Eun Joo;Cho, Jun Cheol;Lee, Hae Kwang
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.4
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    • pp.323-327
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    • 2013
  • Various indicators representing skin characteristics such as skin hydration, sebum excretion rate, lightness, and pH are different depending on environmental and genetic factors. However, they are absolute skin indicators and are different from skin characteristics that a person recognizes. Based on this fact, many recent studies have been mainly conducting researches on perspective changes according to changes of absolute skin. This study was proposed not only to find out differences on skin colors of asian by nations, but also to find out whether there was any difference in skin brightness they perceive depending on actual skin color changing. As many as 410 subjects of three Asia nations were participated in this study, and investigated their responses on skin brightness using questionnaire, which was answered their skin color in three different levels. It was also were analyzed how actual skin brightness were changed depending on their perceived skin color changes of subjects. There was a trend showing that the brightness of the actual skin color was increased when participants felt their skin color got brighter regardless of their nationalities. However, there were some differences in color between perceived color and actual color. In addition, there was a different aspect by nations in changes of skin redness and skin yellowness. In conclusion, it was revealed that factors which help people to perceive their own skin brightness were not based on absolute skin brightness, but on different criteria depending on where they are from.