• Title/Summary/Keyword: JBS

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Quality Characteristics and Manufacture of Mulberry Wine (오디 와인 제조 및 품질특성)

  • Jung Gi-Tai;Ju In-Ok;Choi Dong-Geun
    • Food Science and Preservation
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    • v.12 no.1
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    • pp.90-94
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    • 2005
  • To poodnce a value added of mulberry, this study was optimized the condition for manufacture of wine using mulberry. On fermentation of mulberry wine, the best yeasts were Saccharomyces cerevisiae JBS 30 and JBS 33, and optimum composition of medium was crushed mulberry juice of $50\%$, sugar of $24\;^{\circ}brix,\;Na_2S_2O_5\;of\;0.02\%$. The content of alcohol after fermentation of 10 days at $25^{\circ}C$ was $11.2\%$. Sensory evaluation showed that color, taste and odor of mulberry wine were acceptable, and Saccharomyces cerevisiae JBS 30 was not difference compared to JBS 33.

Observations of the Aurora by Visible All-Sky Camera at Jang Bogo Station, Antarctica

  • Jee, Geonhwa;Ham, Young-Bae;Choi, Yoonseung;Kim, Eunsol;Lee, Changsup;Kwon, Hyuckjin;Trondsen, Trond S.;Kim, Ji Eun;Kim, Jeong-Han
    • Journal of Astronomy and Space Sciences
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    • v.38 no.4
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    • pp.203-215
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    • 2021
  • The auroral observation has been started at Jang Bogo Station (JBS), Antarctica by using a visible All-sky camera (v-ASC) in 2018 to routinely monitor the aurora in association with the simultaneous observations of the ionosphere, thermosphere and magnetosphere at the station. In this article, the auroral observations are introduced with the analysis procedure to recognize the aurora from the v-ASC image data and to compute the auroral occurrences and the initial results on their spatial and temporal distributions are presented. The auroral occurrences are mostly confined to the northern horizon in the evening sector and extend to the zenith from the northwest to cover almost the entire sky disk over JBS at around 08 MLT (magnetic local time; 03 LT) and then retract to the northeast in the morning sector. At near the magnetic local noon, the occurrences are horizontally distributed in the northern sky disk, which shows the auroral occurrences in the cusp region. The results of the auroral occurrences indicate that JBS is located most of the time in the polar cap near the poleward boundary of the auroral oval in the nightside and approaches closer to the oval in the morning sector. At around 08 MLT (03 LT), JBS is located within the auroral oval and then moves away from it, finally being located in the cusp region at the magnetic local noon, which indicates that the location of JBS turns out to be ideal to investigate the variabilities of the poleward boundary of the auroral oval from long-term observations of the auroral occurrences. The future plan for the ground auroral observations near JBS is presented.

Ground-based Observations of the Polar Region Space Environment at the Jang Bogo Station, Antarctica

  • Kwon, Hyuck-Jin;Lee, Changsup;Jee, Geonhwa;Ham, Young-Bae;Kim, Jeong-Han;Kim, Yong Ha;Kim, Khan-Hyuk;Wu, Qian;Bullett, Terence;Oh, Suyeon;Kwak, Young-Sil
    • Journal of Astronomy and Space Sciences
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    • v.35 no.3
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    • pp.185-193
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    • 2018
  • Jang Bogo Station (JBS), the second Korean Antarctic research station, was established in Terra Nova Bay, Antarctica ($74.62^{\circ}S$ $164.22^{\circ}E$) in February 2014 in order to expand the Korea Polar Research Institute (KOPRI) research capabilities. One of the main research areas at JBS is space environmental research. The goal of the research is to better understand the general characteristics of the polar region ionosphere and thermosphere and their responses to solar wind and the magnetosphere. Ground-based observations at JBS for upper atmospheric wind and temperature measurements using the Fabry-Perot Interferometer (FPI) began in March 2014. Ionospheric radar (VIPIR) measurements have been collected since 2015 to monitor the state of the polar ionosphere for electron density height profiles, horizontal density gradients, and ion drifts. To investigate the magnetosphere and geomagnetic field variations, a search-coil magnetometer and vector magnetometer were installed in 2017 and 2018, respectively. Since JBS is positioned in an ideal location for auroral observations, we installed an auroral all-sky imager with a color sensor in January 2018 to study substorms as well as auroras. In addition to these observations, we are also operating a proton auroral imager, airglow imager, global positioning system total electron content (GPS TEC)/scintillation monitor, and neutron monitor in collaboration with other institutes. In this article, we briefly introduce the observational activities performed at JBS and the preliminary results of these observations.

Observations of the Polar Ionosphere by the Vertical Incidence Pulsed Ionospheric Radar at Jang Bogo Station, Antarctica

  • Ham, Young-Bae;Jee, Geonhwa;Lee, Changsup;Kwon, Hyuk-Jin;Kim, Jeong-Han;Zabotin, Nikolay;Bullett, Terence
    • Journal of Astronomy and Space Sciences
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    • v.37 no.2
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    • pp.143-156
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    • 2020
  • Korea Polar Research Institute (KOPRI) installed an ionospheric sounding radar system called Vertical Incidence Pulsed Ionospheric Radar (VIPIR) at Jang Bogo Station (JBS) in 2015 in order to routinely monitor the state of the ionosphere in the auroral oval and polar cap regions. Since 2017, after two-year test operation, it has been continuously operated to produce various ionospheric parameters. In this article, we will introduce the characteristics of the JBS-VIPIR observations and possible applications of the data for the study on the polar ionosphere. The JBS-VIPIR utilizes a log periodic transmit antenna that transmits 0.5-25 MHz radio waves, and a receiving array of 8 dipole antennas. It is operated in the Dynasonde B-mode pulse scheme and utilizes the 3-D inversion program, called NeXtYZ, for the data acquisition and processing, instead of the conventional 1-D inversion procedure as used in the most of digisonde observations. The JBS-VIPIR outputs include the height profiles of the electron density, ionospheric tilts, and ion drifts with a 2-minute temporal resolution in the bottomside ionosphere. With these observations, possible research applications will be briefly described in combination with other observations for the aurora, the neutral atmosphere and the magnetosphere simultaneously conducted at JBS.

Studies on Manufacture of Wine using Apricot (살구를 이용한 와인 제조)

  • Jung, Gi-Tai;Ju, In-Ok;Ryu, Jeong;Choi, Joung-Sik;Choi, Yeong-Geun
    • Food Science and Preservation
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    • v.10 no.4
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    • pp.493-497
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    • 2003
  • In order to prevent a markdown and improve a value added of apricot, this study was conducted to research the optimum condition for manufacture of wine using apricot. On fermentation of aprirot wine, the best yeasts were Saccharomyces cerevisiae JBS 15 and JBS 30, and optimum composition or medium was apricot juice of 50%, sugar of 24 。brix, (NH$_4$)$_2$SO$_4$ of 0.2%, Na$_2$SO$_3$ of 0.02%. The content of alcohol in this medium after fermentation of 10 days at 25$^{\circ}C$ was 12.3∼12.5%. sensory evaluation showed that color, taste and odor or apricot wine were good, and saccharomyces cerevisiae JBS 15 was not difference JBS 30.

Electrical Characteristics of 4H-SiC Junction Barrier Schottky Diode (4H-SiC JBS Diode의 전기적 특성 분석)

  • Lee, Young-Jae;Cho, Seulki;Seo, Ji-Ho;Min, Seong-Ji;An, Jae-In;Oh, Jong-Min;Koo, Sang-Mo;Lee, Deaseok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.6
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    • pp.367-371
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    • 2018
  • 1,200 V class junction barrier schottky (JBS) diodes and schottky barrier diodes (SBD) were simultaneously fabricated on the same 4H-SiC wafer. The resulting diodes were characterized at temperatures from room temperature to 473 K and subsequently compared in terms of their respective I-V characteristics. The parameters deduced from the observed I-V measurements, including ideality factor and series resistance, indicate that, as the temperature increases, the threshold voltage decreases whereas the ideality factor and barrier height increase. As JBS diodes have both Schottky and PN junction structures, the proper depletion layer thickness, $R_{on}$, and electron mobility values must be determined in order to produce diodes with an effective barrier height. The comparison results showed that the JBS diodes exhibit a larger effective barrier height compared to the SBDs.

A study on I-V characteristics in JBS rectifiers according to PN junction structures (JBS(Junction Barrier-controlled Schottky)정류기의 PN접합구조에 따른 I-V 특성에 관한 연구)

  • 안병목;정원채
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.1
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    • pp.13-20
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    • 2000
  • In this paper, we demonstrated an analytical description method of forward votage drop and reverse leakage current of the junction barrier controlled schottky rectifier with linearly graded junction and abrupt junction models. In this case, the vertical depths of device are 1[${\mu}{\textrm}{m}$] and 2[${\mu}{\textrm}{m}$], respectively. Through ion implantation and annealing process, we obtain the data of lateral and depth from implanted 2-dimensional profiles. Also we applied these data to models that indicate the change of depletion each on linearly-graded and abrupt juction as the forward and revers bias. After applied depletion changes to electric characteristics of JBS rectifiers, we calculated the forward I-V, the reverse leakage current and temperatures vs. power dissipations according to each junction. When we compared the rectifier with calculated and measured data, from the calculated results, forward votage drop with linearly graded junction is lower than that of abrupt junction and reverse leakage current with linearly graded junction is lower(≒1$\times$10\ulcorner times) than that of abrupt junction. Also, the power dissipations according to different juction depth(1[${\mu}{\textrm}{m}$], 2[${\mu}{\textrm}{m}$]) of device are calculated. Seeing the calculated results, we confirmed it from analytic model that the rectifier with linearly graded junction retained a low power dissipation up to 600[$^{\circ}C$] in comparison with the rectifier with abrupt junction.

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