• Title/Summary/Keyword: BTD

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A Role for buttonhead in the Early Head and Trunk Development in the Beetle Tribolium castaneum

  • Jeon, Haewon;O, Jiyun;Jin, Sil;Lim, Jinsung;Choe, Chong Pyo
    • Development and Reproduction
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    • v.23 no.1
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    • pp.63-72
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    • 2019
  • The head gap gene buttonhead (btd) is required for the patterning of head segments in the early Drosophila embryo. Mutant phenotypes of btd display a gap-like phenotype in which antennal, intercalary, mandibular and the anterior portion of the maxillary segments are eliminated. In agreement with the phenotypes, btd is expressed in a stripe covering the head segments at the blastoderm stage. During the early phase of the germband extension, btd is expressed in stripes with single segmental periodicity, which is required for the formation of the peripheral nervous system. In contrast to the key role of btd in Drosophila embryonic development, it has been suggested that Tribolium ortholog of btd (Tc-btd) is dispensable for embryonic head development. In order for better understanding of the requirement of Tc-btd in the early Tribolium embryo, we re-analyzed the expression patterns and functions of Tc-btd during embryonic segmentation. Tc-btd is expressed in segmental stripes at the stages of blastoderm and germband elongation. Up to 28.3% of embryos in which Tc-btd is knocked down displays the loss of antennal, mandibular and the pregnathal regions in the head, with abdominal segments being disrupted in the trunk. Our findings suggest that Tc-btd is required for the head and trunk development in the early Tribolium embryo.

BTD Analysis around Corporate Tax Rate Changes (법인세율 변화기간의 연도별 BTD 분석)

  • Park, Su-Gyeong;Rui, Jia
    • Journal of Convergence for Information Technology
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    • v.10 no.1
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    • pp.75-81
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    • 2020
  • This study analyzed the annual difference of firm's book income, taxable income and BTD that before and after the 2009 corporate tax rate cut and 2018 corporate tax rate increase. ANOVA analysis was performed for each item by year, and post hoc was performed after homogeneity test of variance. The research results are as follows. First, the book income at corporate tax rate cut was higher than taxable income, and BTD in 2008 was significantly different from other years. Second, the book income at corporate tax rate increase was less than taxable income, and BTD in 2017 was also significantly different from other years. In other words, the firm is performing appropriate profit adjustments to reduce of tax burden when the corporate tax rate changes. Because of this, the BTD in the year immediately before the corporate tax rate change is different from other years.

THE MODIFIED BRIGHTNESS TEMPERATURE DIFFERENCE FOR AEROSOL DETECTION

  • Kim, Jae-Hwan;Ha, Jong-Sung;Lee, Hyun-Jin
    • Proceedings of the KSRS Conference
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    • v.2
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    • pp.794-796
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    • 2006
  • This study investigated the Brightness Temperature Difference threshold as criterion between aerosols and clouds in conjunction with radiative transfer model. Surface temperature is caused by a significant error over 50% in the BTD threshold. In addition, The BTD threshold contains the uncertainties about 20% due to the surface emissivity and 8% due to the satellite zenith angle. Therefore, we have composed the Look-up table for BTD between 11㎛and 12㎛ according to satellite zenith angle, surface temperature, and surface emissivity. The modified BTD show the enhanced signal, especially over bright surface such as desert in China. However, a weak aerosol signal over Ocean remains in the modified BTD.

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Study on the Electron Injection of Newly Synthesized Organic Sensitizer in Dye-Sensitized Solar Cell

  • Gang, Tae-Yeon;Lee, Do-Gwon;Go, Min-Jae;Kim, Gyeong-Gon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.310-310
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    • 2010
  • Electronic and photovoltaic characteristics of two sensitizers (TA-BTD-CA and TA-BTD-St-CA), composed of a different $\pi$-conjugation in the linker group, have been investigated by theoretical and experimental methods. The electronic structure, transition dipole moment and oscillator strengths of two sensitizers have been scrutinized by using density functional theory (DFT) and time-dependent DFT (TD-DFT) method. The LUMO level and the oscillator strength of TA-BTD-St-CA was higher than that of TA-BTD-CA, which may facilitate the electron injection process as well as increase the absorption coefficient. The relative efficiencies of the electron injection from the excited sensitizer to nanocrystalline TiO2 and SnO2 films have also been investigated by nanosecond transient absorption spectroscopy. The relative electron injection efficiency of TA-BTD-St-CA exhibited similar injection efficiency for two different semiconductors. However, in the case of TA-BTD-CA sensitizer, electron injection into SnO2 was approximately three times larger than that into TiO2. This enhancement of electron injection of TA-BTD-CA for the SnO2 is due to the increment of the driving force caused by positive shift of conduction band of semiconductor, which was also confirmed from the investigation for the photovoltaic characteristics according to the electrolyte additive, such as LiI additive.

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Sensitivity Analysis of IR Aerosol Detection Algorithm (적외선 채널을 이용한 에어로솔 탐지의 경계값 및 민감도 분석)

  • Ha, Jong-Sung;Lee, Hyun-Jin;Kim, Jae-Hwan
    • Korean Journal of Remote Sensing
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    • v.22 no.6
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    • pp.507-518
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    • 2006
  • The radiation at $11{\mu}m$ absorbed more than at $12{\mu}m$ when aerosols is loaded in the atmosphere, whereas it will be the other way around when cloud is present. The difference of the two channels provides an opportunity to detect aerosols such as Yellow Sand even with the presence of clouds and at night. However problems associated with this approach arise because the difference can be affected by various atmospheric and surface conditions. In this paper, we has analyzed how the threshold and sensitivity of the brightness temperature difference between two channel (BTD) vary with respect to the conditions in detail. The important finding is that the threshold value for the BTD distinguishing between aerosols and cloud is $0.8^{\circ}K$ with the US standard atmosphere, which is greater than the typical value of $0^{\circ}K$. The threshold and sensitivity studies for the BTD show that solar zenith angle, aerosols altitude, surface reflectivity, and atmospheric temperature profile marginally affect the BTD. However, satellite zenith angle, surface temperature along with emissivity, and vertical profile of water vapor are strongly influencing on the BTD, which is as much as of about 50%. These results strongly suggest that the aerosol retrieval with the BTD method must be cautious and the outcomes must be carefully calibrated with respect to the sources of the error.

The Improvement of Infrared Brightness Temperature Difference Method for Detecting Yellow Sand Dust

  • Ha, Jong-Sung;Kim, Jae-Hwan
    • Proceedings of the KSRS Conference
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    • 2007.10a
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    • pp.149-152
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    • 2007
  • The detection of yellow sand dust using satellite has been utilized from various bands from ultraviolet to infrared channels. Among them, Infrared channels have an advantage of detecting aerosols over high reflecting surface as well as during nighttime. Especially, brightness temperature difference between 11 and 12{\mu}m(BTD) was often used to distinguish between water cloud and yellow sand, because Ice and liquid water particles preferentially absorb longer wavelengths while aerosol particles preferentially absorb shorter wavelengths. We have found that the BTD significantly depends on surface temperature, emissivity, and zenith angle and thereby the threshold of BTD. In order to overcome these problems, we have constructed the background brightness temperature threshold of BTD and then subtracted it from BTD. Along with this, we utilized high temporal coverage of geostationary satellite, MTSAT-1R, to verify the reliability of the retrieved signal in conjunction with forecasted wind information. The statistical score test illustrated that this newly developed algorithm showed a promising result for detecting mineral dust by reducing the errors in the current BTD method.

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The Detection of Yellow Sand Using MTSAT-1R Infrared bands

  • Ha, Jong-Sung;Kim, Jae-Hwan;Lee, Hyun-Jin
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.236-238
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    • 2006
  • An algorithm for detection of yellow sand aerosols has been developed with infrared bands from Moderate Resolution Imaging Spectroradiometer (MODIS) and Multi-functional Transport Satellite-1 Replacement (MTSAT-1R) data. The algorithm is the hybrid algorithm that has used two methods combined together. The first method used the differential absorption in brightness temperature difference between $11{\mu}m$ and $12{\mu}m$ (BTD1). The radiation at 11 ${\mu}m$ is absorbed more than at 12 ${\mu}m$ when yellow sand is loaded in the atmosphere, whereas it will be the other way around when cloud is present. The second method uses the brightness temperature difference between $3.7{\mu}m$ and $11{\mu}m$ (BTD2). The technique would be most sensitive to dust loading during the day when the BTD2 is enhanced by reflection of $3.7{\mu}m$ solar radiation. We have applied the three methods to MTSAT-1R for derivation of the yellow sand dust and in conjunction with the Principle Component Analysis (PCA), a form of eigenvector statistical analysis. As produced Principle Component Image (PCI) through the PCA is the correlation between BTD1 and BTD2, errors of about 10% that have a low correlation are eliminated for aerosol detection. For the region of aerosol detection, aerosol index (AI) is produced to the scale of BTD1 and BTD2 values over land and ocean respectively. AI shows better results for yellow sand detection in comparison with the results from individual method. The comparison between AI and OMI aerosol index (AI) shows remarkable good correlations during daytime and relatively good correlations over the land.

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Detection of Yellow Sand Dust over Northeast Asia using Background Brightness Temperature Difference of Infrared Channels from MODIS (MODIS 적외채널 배경 밝기온도차를 이용한 동북아시아 황사 탐지)

  • Park, Jusun;Kim, Jae Hwan;Hong, Sung Jae
    • Atmosphere
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    • v.22 no.2
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    • pp.137-147
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    • 2012
  • The technique of Brightness Temperature Difference (BTD) between 11 and $12{\mu}m$ separates yellow sand dust from clouds according to the difference in absorptive characteristics between the channels. However, this method causes consistent false alarms in many cases, especially over the desert. In order to reduce these false alarms, we should eliminate the background noise originated from surface. We adopted the Background BTD (BBTD), which stands for surface characteristics on clear sky condition without any dust or cloud. We took an average of brightness temperatures of 11 and $12{\mu}m$ channels during the previous 15 days from a target date and then calculated BTD of averaged ones to obtain decontaminated pixels from dust. After defining the BBTD, we subtracted this index from BTD for the Yellow Sand Index (YSI). In the previous study, this method was already verified using the geostationary satellite, MTSAT. In this study, we applied this to the polar orbiting satellite, MODIS, to detect yellow sand dust over Northeast Asia. Products of yellow sand dust from OMI and MTSAT were used to verify MODIS YSI. The coefficient of determination between MODIS YSI and MTSAT YSI was 0.61, and MODIS YSI and OMI AI was also 0.61. As a result of comparing two products, significantly enhanced signals of dust aerosols were detected by removing the false alarms over the desert. Furthermore, the discontinuity between land and ocean on BTD was removed. This was even effective on the case of fall. This study illustrates that the proposed algorithm can provide the reliable distribution of dust aerosols over the desert even at night.

Supplementation of a Fermented Soybean Extract Reduces Body Mass and Prevents Obesity in High Fat Diet-Induced C57BL/6J Obese Mice

  • Lee, Jae Yeon;Aravinthan, Adithan;Park, Young Shik;Hwang, Kyo Yeol;Seong, Su-Il;Hwang, Kwontack
    • Preventive Nutrition and Food Science
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    • v.21 no.3
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    • pp.187-196
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    • 2016
  • Obesity is a growing health problem that many countries face, mostly due to the consumption of a Westernized diet. In this present study we observed the effects of a soybean extract fermented by Bacillus subtilis MORI (BTD-1) containing 1-deoxynojirimycin against high fat diet-induced obesity. The results obtained from this study indicated that BTD-1 reduced body weight, regulated hepatic lipid content and adipose tissue, and also affected liver antioxidant enzymes and glucose metabolism. These results suggest that administration of BTD-1 affects obesity by inhibiting hyperglycemia and free radical-mediated stress; it also reduces lipid accumulation. Therefore, BTD-1 may be potentially useful for the prevention of obesity and its related secondary complications.

The Detection of Yellow Sand with Satellite Infrared bands

  • Ha, Jong-Sung;Kim, Jae-Hwan;Lee, Hyun-Jin
    • Korean Journal of Remote Sensing
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    • v.22 no.5
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    • pp.403-406
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    • 2006
  • An algorithm for detection of yellow sand aerosols has been developed with infrared bands. This algorithm is a hybrid algorithm that has used two methods combined. The first method used the differential absorption in brightness temperature difference between $11{\mu}m\;and\;12{\mu}m\;(BTD1)$. The radiation at $11{\mu}m$ is absorbed more than at $12{\mu}m$ when yellow sand is loaded in the atmosphere, whereas it will be the other way around when cloud is present. The second method uses the brightness temperature difference between $3.7{\mu}m\;and\;11{\mu}m(BTD2)$. This technique is sensitive to dust loading, which the BTD2 is enhanced by reflection of $3.7{\mu}m$ solar radiation. First the Principle Component Analysis (PCA), a form of eigenvector statistical analysis from the two methods, is performed and the aerosol pixel with the lowest 10% of the eigenvalue is eliminated. Then the aerosol index (AI) from the combination of BTD 1 and 2 is derived. We applied this method to Multi-functional Transport Satellite-l Replacement (MTSAT-1R) data and obtained that the derived AI showed remarkably good agreements with Ozone Mapping Instrument (OMI) AI and Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol optical depth.