• Title/Summary/Keyword: Package atmosphere

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Vacuum Packaging of MEMS (Microelectromechanical System) Devices using LTCC (Low Temperature Co-fired Ceramic) Technology (LTCC 기술을 이용한 MEMS 소자 진공 패키징)

  • 전종인;최혜정;김광성;이영범;김무영;임채임;황건탁;문제도;최원재
    • Journal of the Microelectronics and Packaging Society
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    • v.10 no.1
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    • pp.31-38
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    • 2003
  • In the current electronic technology atmosphere, MEMS (Microelectromechanical System) technology is regarded as one of promising device manufacturing technologies to realize market-demanding device properties. In the packaging of MEMS devices, the packaged structure must maintain hermeticity to protect the devices from a hostile atmosphere during their operations. For such MEMS device vacuum packaging, we introduce the LTCC (Low temperature Cofired Ceramic) packaging technology, in which embedded passive components such as resistors, capacitors and inductors can be realized inside the package. The technology has also the advantages of the shortened length of inner and surface traces, reduced signal delay time due to the multilayer structure and cost reduction by more simplified packaging processes owing to the realization of embedded passives which in turn enhances the electrical performance and increases the reliability of the packages. In this paper, the leakage rate of the LTCC package having several interfaces was measured and the possibility of LTCC technology application to MEMS devices vacuum packaging was investigated and it was verified that improved hermetic sealing can be achieved for various model structures having different types of interfaces (leak rate: stacked via; $4.1{\pm}1.11{\times}10^{-12}$/ Torrl/sec, LTCC/AgPd/solder/Cu-tube; $3.4{\pm}0.33{\times}10^{-12}$/ Torrl/sec). In real application of the LTCC technology, the technology can be successfully applied to the vacuum packaging of the Infrared Sensor Array and the images of light-up lamp through the sensor way in LTCC package structure was presented.

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THE SOLAR-B MISSION

  • ICHIMOTO KIYOSHI;TEAM THE SOLAR-B
    • Journal of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.307-310
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    • 2005
  • The Solar-B is the third Japanese spacecraft dedicated for solar physics to be launched in summer of 2006. The spacecraft carries a coordinated set of optical, EUV and X-ray instruments that will allow a systematic study of the interaction between the Sun's magnetic field and its high temperature, ionized atmosphere. The Solar Optical Telescope (SOT) consists of a 50cm aperture diffraction limited Gregorian telescope and a focal plane package, and provides quantitative measurements of full vector magnetic fields at the photosphere with spatial resolution of 0.2-0.3 arcsec in a condition free from terrestrial atmospheric seeing. The X-ray telescope (XRT) images the high temperature (0.5 to 10 MK) corona with improved spatial resolution of approximately 1 arcsec. The Extreme Ultraviolet Imaging Spectrometer (EIS) aims to determine velocity fields and other plasma parameters in the corona and the transition region. The Solar-B telescopes, as a whole, will enable us to explore the origins of the outer solar atmosphere, the corona, and the coupling between the fine magnetic structure at the photosphere and the dynamic processes occurring in the corona. The mission instruments (SOT/EIS/XRT) are joint effort of Japan (JAXA/NAO), the United States (NASA), and the United Kingdom (PPARC). An overview of the spacecraft and its mission instruments are presented.

The Development of Automatic Production System of Agricultural Weather Information Using the Biosphere-Atmosphere Transfer Scheme (BATS) (지표대기모형 BATS를 이용한 농업기상정보 자동산출시스템 개발)

  • Shin Hyun-Cheol;Suh Ae-Sook;Lee Sun-Mi
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.1 no.2
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    • pp.135-141
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    • 1999
  • The information on agricultural weather over the Korean Peninsula was produced, using the Bio-sphere-Atmosphere Transfer Scheme(BATS). We modified the input and output portions of BATS such that the whole processes can be excuted as a package. Based on this approach, automatic production system of agricultural meteorology information was developed. The results of this model was compared with the observed data. The differences between the model results and observed data for surface temperature, rooting zone temperature and top soil temperature were 2.0$^{\circ}$C, 2.0$^{\circ}$C and 2.6$^{\circ}$C, respectively.

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Model development to design modified atmosphere packaging of Mandarin oranges

  • Kim, Jong-Kyoung;Lee, Sang-Duk;Ha, Young-Sun;Lee, Jun-Ho
    • Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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    • 2003.10a
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    • pp.192.1-192
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    • 2003
  • The aim of this study was to develop a model that could be used in the design of modified atmosphere packaging (MAP) for Mandarin oranges. Respiratory data at 5, 10, 20$^{\circ}C$ for mandarin oranges were gathered and altered for create useful respiration model. The maximum rate of oxygen uptake increased with increasing temperature. The packaging materials were conventional low density polyethylene and polypropylene with anti-fog, and anti-fungi treatments, and thickness was 30 $\mu\textrm{m}$ and 50 $\mu\textrm{m}$. Permeability tests were performed to find their oxygen, carbon dioxide, water vapor transmission rate as increases in temperature. Test results were then converted to logarithm format for MAP modeling. Optimum gas composition in the package system for fruits were set according to literature and upper or lower limits of oxygen and dioxide established. To predict gas composition at certain storage time, weight of fruits, film thickness, film type, and other variables, respiration rate was studied at various storage conditions. The validity of the model was tested experimentally by observing actual atmospheric changes inside packages. It is concluded that the strategy developed is of use in designing dynamic gas exchange MAP systems, and also has potential uses in similar agricultural products.

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Effect of Modified Atmosphere Packaging on Preservation of Pumpkin Rice Cake (호박 설기떡의 저장성에 미치는 변형기체포장의 영향)

  • Moon, Ki-Bok;Kim, Hwan-Ki;An, Duck-Soon;Lee, Dong-Sun
    • Food Science and Preservation
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    • v.17 no.6
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    • pp.908-913
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    • 2010
  • Modified atmosphere packaging (MAP) was evaluated for the storage of pumpkin rice cake as a means of preserving quality and extending shelf-life. Retail-sized amounts of rice cake were packaged in trays under different modified atmosphere conditions (air, vacuum, 60% $CO_2$/40% $N_2$ and 100% $CO_2$) using gas-barrier plastic film; control was in air-permeable stretch wrap. The packages were stored at $20^{\circ}C$ with periodical measurement of package atmosphere and cake quality attributes. The modified atmosphere packages of 60% $CO_2$/40% $N_2$ and 100% $CO_2$ inhibited the growth of molds/yeasts completely and significantly retarded the growth of aerobic bacteria. All the packages except that of 100% $CO_2$ showed the reduction of internal $O_2$ concentration and increase of the $CO_2$ with storage time due to the microbial activity. There has been slight decrease of $CO_2$ concentration for 60% $CO_2$/40% $N_2$ and 100% $CO_2$ packages just after start of the storage possibly due to dissolution of headspace $CO_2$ into the cake. Any MAP conditions did not affect the retrogradation of the rice cake. Surface color of the cake within affordable microbial quality limit was not affected significantly by packaging conditions.

Effects of combination treatment with sulfur dioxide generating pad and modified atmosphere packaging (MAP) on the quality of 'Campbell Early'grape under simulated export conditions (모의수출조건에서 유황패드와 MAP 복합처리가 '캠벨얼리' 포도의 품질에 미치는 영향)

  • Choi, Mi-Hee;Lee, Jin-Su;Lim, Byung-Seon
    • Food Science and Preservation
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    • v.24 no.6
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    • pp.734-745
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    • 2017
  • The effects of combination treatment with sulfur dioxide generating pad ($SO_2$ pad) and modified atmosphere packaging (MAP) on grape quality were examined under simulated exporting condition and actual export to Los Angeles, USA. The 'Campbell Early' grape harvested in Hwaseong, Gyeonggi was precooled at $0^{\circ}C$, selected and packaged at $10^{\circ}C$, and stored at $0^{\circ}C$ for 30 days. The treatment was as follows: general export packaging (control), only $SO_2$ pad, combination of $SO_2$ pad and MAP (perforated polyethylene film, $SO_2$ pad+MA). In case of control and only $SO_2$ pad under simulated exporting condition, the grape quality changes with storage time were decrease in hardness and brush length, increase in stem browning, and increased in shattering rate. The treatment of $SO_2$ pad+MA was the most effective in preserving the grape quality since $SO_2$ concentration inside the package remained around 2.9 ppm by MA film. Grape exports from harvest to local distribution of the USA took 30 days, and only $SO_2$ pad+MA package showed no fungus, maintained brush length and rachis color, and was lowest at 4.0% of shattering rate since the concentration of $SO_2$ in the package was about 4.0 ppm. As a result, it was considered that the combination of $SO_2$ pad and MA was the most effective way to maintain freshness of grape during long-term marine transportation and extend the shelf-life in exporting countries.

Computer Modeling of Modified Atmosphere Packaging of Peaches (복숭아의 환경기체조절포장을 위한 컴퓨터 모델링)

  • Kim, Jong-Kyoung;Ha, Young-Sun;Lee, Jun-Ho;Lee, Sang-Duk;Kim, Jae-Neung
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.9 no.1
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    • pp.33-54
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    • 2003
  • The aim of this study was to develop a model that could be used in the design of modified atmosphere packaging (MAP) for peaches. Respiratory data at 5, 10, $20^{\circ}C$ for peaches were gathered and altered for create useful respiration model. Packaging materials were conventional low density polyethylene and polypropylene with anti-fog, and anti-fungi treatments, and thickness was $30{\mu}m$ and $50{\mu}m$ each. Permeability tests were performed to find their oxygen, carbon dioxide, water vapor transmission rate as increases in temperature. Test results were then converted to logarithm format for MAP modeling. The maximum rate of oxygen uptake increased with increasing temperature. Optimum gas composition in the package system for fruits were set according to literature and upper or lower limits of oxygen and dioxide established. To predict gas composition at certain storage time, weight of fruits, film thickness, film type, and other variables, respiration rate was studied at various storage conditions. The results of tests were used to calculate Cameron's model and converted to a cubic estimation equation. The validity of the model was tested experimentally by observing actual atmospheric changes inside packages. This result of study may be useful for designing dynamic gas exchange MAP systems for similar agricultural products.

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A Study on University Student's Recognition and Preference of Korean Rice Cake in Incheon Area (인천지역 대학생의 떡의 인지도 및 기호도에 관한 연구)

  • 노정옥;우경자
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.1
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    • pp.1-8
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    • 2003
  • The purpose of this study was to investigate the university students' recognition and preference of Korean rice cakes. Self administered questionnaires were collected from 302 students in Incheon area. Statistical data analysis was completed using a SPSS 10.0 program. The recognition of Korean rice cake was generally high: Injeolmi, Garaeddeok, Bakseolgi, Songpyun, Patsirooddeok, Bindaeddeok, Yaksik Julpyun, Gyungdan, Moojigaeddeok were high1y recognized, but Gaesungjooak, Sugyibyung, Seunggeomchopyun poorly recognized by university students. The most common consumption frequency rate of students was once or twice a month (Male 31.9%; Female 41.6%). Most students ate rice cakes as snack with water, Kimchi, fruits, beverage(Cola, Cider) and Korean traditional beverage(Sujunggwa, Sighye). The sales possibility of Korean rice cake at university canteens was dependent on the characteristics different from those of rice cafes itself, for example,. nutritional labelling, mass, atmosphere and package, etc.

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Modified PZT System for Pyroelectric IR Sensor (Modified PZT계 초전형 적외선 센서개발)

  • 황학인;박준식;오근호
    • Journal of the Korean Ceramic Society
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    • v.33 no.8
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    • pp.863-870
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    • 1996
  • Fabricated modified PZT system for pyroelectric IR sensor were analyzed and characterized for dielectric piezoelectric and pyroelectric properties. Particle size and distribution of source powders were controlled by attrition milling process. 0.05PSS+yPT+(0.95-y)PZ+0.4 wt%MnO2 system was fabricated and investigated sintering density crystal structure and micro-structure through sintering conditions sintering temperature and sintering atmosphere. The poled sintered system of y=0.11 showed the lowest dielectric constant. The dielectric constants were increased with increasing y-mole ratio. The pyroelectric properties of modified PZT systems which were assembled to TO-5 package were measured by IR measurement system average out-voltage of 0.05PSS+0.1PT+0.84PZ+ wt%MnO2 was 3V.

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SPECTRAL LINE-DEPTH RATIO AS A PRECISE EFFECTIVE TEMPERATURE AND SURFACE GRAVITY INDICATOR FOR WARM STARS

  • Kim, Chul-Hee
    • Journal of The Korean Astronomical Society
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    • v.39 no.4
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    • pp.125-128
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    • 2006
  • In order to determine the precise effective temperature and surface gravity of warm stars, all synthetic spectral lines in the wavelength range of $4000-5700{\AA}$ with T=6000-7750 K, and log g=3.5, 4.0, and 4.5 for [M/H]=0.0, $V_{rot}$=10 km $s^{-1}$, and $V_{tubl}$=2 km $s^{-1}$ were calculated using the SYNSPEC package(Hubeny, et al., 1995) and the Kurucz(1995) model. Then, the depth-ratios for all line pairs were investigated and we selected two and six depth-ratios appropriate for the surface gravity and temperature indicators, respectively. We plotted six grids with X- and Y-axes for the depth-ratios of surface gravity and temperature, respectively, for the simultaneous estimation of these two atmospheric parameters. This method was applied to the spectum of $\delta$ Scu for the determination of its temperature and surface gravity simultaneously.