• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.19 no.6
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• pp.87-93
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• 2019

We discuss the design of a radiometer using a millimeterwave(Ka-band) seeker. We applied a total power radiometer, thus the radiometer is composed of a IF-drive amp, band-pass filter, detector and an Op-amp additionally. As a radiometer measure a radiated signal of an object which is noise-like, a radiometer is easily affected by the variance of system temperature. To mitigate an adverse effect, we propose a compensation method in a radiometer without brightmess temperature compensation circuits. Through some experiments such like a distinction a target and the background, we have verified that the designed radiometer system has distingushed a car from the ground completely.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.168-168
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• 2010

Transparent conduction oxides (TCOs) films is extensively reported for optoelectronic devices application such as touch panels, solar cells, liquid crystal displays (LCDs), and organic light emitting diodes(OLEDs). Among the many TCO film, indium tin oxide(ITO) is in great demand due to the growth of flat panel display industry. However, indium is not only high cost but also its deposits dwindling. Therefore, many studies are being done on the transparent conductive oxides(TCOs). We fabricated a target of IZTO(In2O3:ZnO:SnO2=70:15:15 wt.%) reduced indium. Then, IZTO thin films were deposited on glass substrates by pulsed DC magnetron sputtering with various oxygen flow ratio. The substrate temperature was fixed at the room temperature. We investigated the electrical, optical, structural properties of IZTO thin films. The electrical properties of IZTO thin films were dependent on the oxygen partial pressure. As a result, the most excellent properties of IZTO thin films were obtained at the 3% of oxygen flow rate with the low resistivity of $7.236{\times}10^{-4}{\Omega}cm$. And also the optical properties of IZTO thin films were shown the good transmittance over 80%. These IZTO thin films were used to fabricated organic light emitting diodes(OLEDs) as anode and the device performances studied. The OLED with an IZTO anode deposited at optimized deposition condition showed good brightness properties. Therefore, IZTO has utility value of TCO electrode although it reduced indium and we expect it is possible for the IZTO to apply to flexible display due to the low processing temperature.

• Korean Journal of Materials Research
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• v.23 no.12
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• pp.727-731
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• 2013

In this study, green barium strontium silicate phosphor ($BaSrSiO_4:Eu^{3+}$, $Eu^{2+}$) was synthesized using a solid-state reaction method in air and reducing atmosphere. Investigation of the firing temperature indicates that a single phase of $BaSrSiO_4$ is formed when the firing temperature is higher than $1400^{\circ}C$. The effect of firing temperature and doping concentration on luminescent properties are investigated. The light-emitting property was the best when the molar content of $Eu_2O_3$ was 0.025 mol. Also, the luminescent brightness of the $BaSrSiO_4$ fluorescent substance was the best when the particle size of the barium was $0.5{\mu}m$. $BaSrSiO_4$ phosphors exhibit the typical green luminescent properties of $Eu^{3+}$ and $Eu^{2+}$. The characteristics of the synthesized $BaSrSiO_4:Eu^{3+}$, $Eu^{2+}$ phosphor were investigated using X-ray diffraction (XRD) and scanning electron microscopy. The maximum emission band of the $BaSrSiO_4:Eu^{3+}$, $Eu^{2+}$ was 520 nm.

• Journal of the Korean Society of Food Culture
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• v.20 no.6
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• pp.715-720
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• 2005

Jeolpyon rice cake was made using buckwheat flour and measured its texture, color and sensory properties as follows. According to the amylograph guage test, rice flour was the highest in its initial pasting temperature $82.5^{\circ}C$. With 5% addition of buckwheat flour, it came to be $81.0^{\circ}C$ and became $79.5^{\circ}C$ at 10%, and $78.0^{\circ}C$ at 15%, which was lower than the control. And its maximum temperature at peak viscosity showed at $87^{\circ}C$ and it showed no difference in temperature according to the amount of buckwheat flour. The maximum value (peak point) was 690 BU in control and it increased following to the added amount of buckwheat flour, 710 BU in adding buckwheat flour 10% and 740 BU in 15% of buckwheat flour. In relating to the changes of texture, it became hard by the added amount of buckwheat flour because of decreasing cohesiveness and springiness, but increasing gumminess and brittleness. The hardness increased by adding with buckwheat flour through the freeze preserving period. But adding buckwheat flour of 10% decreased the hardness. Regarding the color value, lightness decreased by the adding buckwheat flour, but a and b value increased. As a result of the sensory analysis about Jeolpyon prepared with buckwheat flour, the most favoured ratio of buckwheat flour for color and preference was at 10%. In case of 15%, it was a little dark so it was not desirable. Based on the above test, the best combination ratio of buckwheat for Jeolpyon was 10%. And Jeolpyon can be easily made at home as well as mass production due to relatively simple making procedure.

• International Union of Geodesy and Geophysics Korean Journal of Geophysical Research
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• v.21 no.1
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• pp.47-54
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• 1993

The major positive sea surface temperature(SST) anomalies not only occur in the region with the most moisture increase, but also in the flank of the area with sinking motion in the Subtropics. As the large amount of water vapor has been increased by the SST anomaly, the increased of the SST is expected to destabilize the air and leads under moist adiabatic unstable conditions, to an enhanced development of moisture cluster. The 4.0 K change of SST causes the positive difference of Brightness Temperature(TB) of about 10.0k for water vapor channels of TOVS over the north eastern and central tropical Pacific Ocean, but the negative difference of TB of about 7.5 K is shifted southward and southeastward to Southern Pacific Ocean along the equator correspondingly. The difference of the TBs for IR water vapor channel $11(7.3{\mu}m)$ and $12(6.7{\mu}m)$ of TOVS indicative of the moisture distribution during two time periods(January 1983 and 1984), leads us to infer significant changes in the entire tropospheric circulations and the dynamic processes over the Pacific Ocean.

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.228-235
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• 2008

In this study, vinegar disinfection was evaluated as a novel method for the preparation of raw food ingredients used in foodservice operations. The test materials were washed and disinfected using three different methods, and were then stored at temperatures of $3^{\circ}C\;and\;10^{\circ}$ for 7 days; Following storage, physicochemical and sensory characteristic comparisons were performed. Temperature for all test materials ranged between 15.2-20. $9^{\circ}C$, water activity was maintained near 0.96, and the pH levels of the samples were 6.44, 6.29, and 6.35, respectively. Residual chlorine levels were generally low, ranging between 0.01 and 0.02. The physicochemical qualities of the samples were evaluated according to the storage method and temperature. Brightness(L value), redness(a value), and yellowness(b value) tended to increase with increasing storage time. The evaluated sensory characteristics included appearance, color, smell, taste, texture, and overall acceptance. With regard to storage temperature the vinegar-treated samples were evaluated as superior, receiving a score of 7.00, and the ingredients stored at $3^{\circ}C$ were evaluated as significantly (p< 0.001) superior to those stored at $10^{\circ}C$. Overall, vinegar is an effective disinfectant to apply in the preparation of raw vegetables that are typically served without heating, and which can cause serious food safety issues when contaminated.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2019.05a
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• pp.618-620
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• 2019

Smart Farm, which combines agriculture and ICT convergence technology, is at a lower stage than other industries in Korea, but it is also one of the most active research and development fields. Smart Farm aims to improve the efficiency of each step by collecting, processing and analyzing various information of agriculture sector through convergence between agriculture and ICT technology. In this study, we studied the image processing method that can distinguish strawberry which can be harvested at harvest time by color for smart farm composition of strawberry which is a horticultural crop. Strawberry harvesting requires a lot of labor in the process of growing strawberries. In this study, we aim to collect information necessary for labor saving in strawberry harvester. As a precedent study, we plan to implement a form in which the color temperature changes according to the light direction and brightness value through OpenCV color detection using Python. In the future, it is planned to study strawberry color value suitable for harvest by applying compensation value to color temperature change.

• International Journal of Computer Science & Network Security
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• v.21 no.6
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• pp.47-53
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• 2021

The article deals with the problems of application of microwave methods in systems of geoecological monitoring of natural environments and resources of the agro-industrial complex. It is noted that the methods of microwave radiometry make it possible, by the power of the measured intrinsic radio-thermal radiation of the atmosphere, when solving inverse problems using empirical and semi-empirical models, to determine such parameters of the atmosphere as thermodynamic temperature, humidity, water content, moisture content, precipitation intensity, and the presence of different fractions of clouds.In addition to assessing the meteorological parameters of the atmosphere and the geophysical parameters of the underlying surface based on the data of microwave radiometric measurements, it is possible to promptly detect and study pollution of both the atmosphere and the earth's surface. A technique has been developed for the analysis of sources of measurement error and their numerical evaluation, because they have a significant effect on the accuracy of solving inverse problems of reconstructing the values of the physical parameters of the probed media.To analyze the degree of influence of the limited spatial selectivity of the antenna of the microwave radiometric system on the measurement error, we calculated the relative measurement error of the ratio of radio brightness contrasts in two angular directions. It has been determined that in the system of geoecological monitoring of natural environments, the effect of background noise is maximal with small changes in the radiobrightness temperature during angular scanning and high sensitivity of the receiving equipment.

• Korean Journal of Remote Sensing
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• v.32 no.5
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• pp.435-452
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• 2016

Land Surface Temperature (LST) has been operationally retrieved from the Communication, Ocean, and Meteorological Satellite (COMS) data by the spilt-window method (CSW_v2.0) developed by Cho et al. (2015). Although the CSW_v2.0 retrieved the LST with a reasonable quality compared to the Moderate Resolution Imaging Spectroradiometer (MODIS) LST data, it showed a relatively poor performance for the strong inversion and lapse rate conditions. To solve this problem, the LST retrieval algorithm (CSW_v2.0) was updated using the simulation results of radiative transfer model (MODTRAN 4.0) by considering the diurnal variations of air temperature. In general, the upgraded version, CSW_v3.0 showed a similar correlation coefficient between the prescribed LSTs and retrieved LSTs (0.99), the relatively smaller bias (from -0.03 K to-0.012 K) and the Root Mean Square Error (RMSE) (from 1.39 K to 1.138 K). Particularly, CSW_v3.0 improved the systematic problems of CSW_v2.0 that were encountered when temperature differences between LST and air temperature are very large and/or small (inversion layers and superadiabatic lapse rates), and when the brightness temperature differences and surface emissivity differences were large. The bias and RMSE of CSW_v2.0 were reduced by 10-30% in CSW_v3.0. The indirect validation results using the MODIS LST data showed that CSW_3.0 improved the retrieval accuracy of LST in terms of bias (from -0.629 K to -0.049 K) and RMSE (from 2.537 K to 2.502 K) compared to the CSW_v2.0.

• Journal of the Korean earth science society
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• v.21 no.6
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• pp.703-718
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• 2000

In order to investigate interannual variation of total ozone and reflectivity over the globe, Nimbus-7/TOMS data were used on the monthly mean and its anomaly for the period of 1979-92. This study also examined MSU channel 4(Ch4; lower-stratosphere) brightness temperature data and two model reanalyses of NCEP and GEOS to compare the ozone variation with atmospheric thermal condition. In addition, the MSU channel 1(Ch1 ; lower-troposphere) brightness temperature was used to compare with the reflectivity. The ozone showed strong annual cycle with downward trend(-6.3${\pm}$0.6 DU/decade) over the globe, and more distinct response to volcanic eruption than El Ni${\tilde{n}$o. The relationship between total ozone and MSU Ch4 observation, and between the ozone and model reanalyses of lower stratosphere temperature showed positive correlation(0.2-0.7) during the period of 1980-92. Reflectivity increased interannually by 0.2${\pm}$0.06%/decade over the globe during the above period and reflected El Ni${\tilde{n}$o(1982-83, 1991-92) well. Its variability in annual cycle was remarkably smaller in tropics than in higher latitudes. This is inferred due to cloud suppression and tropical upwelling regions. Reflectivity correlated negatively(-0.9) to the Ch1 temperature over the globe, but positively(0.2) over tropical ocean. The positive value over the ocean results from the effect of microwave emissivity which increases the Ch1 temperature with enhanced hydrometeor activity. Significant correlations between total ozone and the Ch4 temperature, and between reflectivity and the Ch1 Suggest that the TOMS data may use valuably to better understand the feedback mechanism of climate change.