• 제목/요약/키워드: Vacuum measurement

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CHARACTERISTICS OF RESIDUAL CARBON DERIVED FROM THE COMBUSTION OF VACUUM RESIDUE IN A TEST FURNACE

  • Park, Ho-Young;Seo, Sang-Il
    • Environmental Engineering Research
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    • v.12 no.3
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    • pp.109-117
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    • 2007

  • The characteristics of carbonaceous particles collected from the combustion of Vacuum Residue (VR) in a test furnace have been investigated. The physical and chemical characterization includes particle size, scanning electron microscopy of the surface structure, measurement of porosity, surface area and density, EDX/XRD analyses and measurement of chemical composition. The studies show that the carbonaceous VR particles are very porous and spheroidal, and have many blow-holes on the surface. The particles become smaller and more sponge-like as the reaction proceeds. The present porosity of VR particles is similar to that of cenospheres from the combustion of heavy oil, and the majority of pores are distributed in macro-pores above $0.03\;{\mu}m$ in diameter. Measurements of pore distribution and surface area showed that the macro-pores contributed most to total pore volume, whereas the micro-pores contributed to total surface area.

  • https://doi.org/10.4491/eer.2007.12.3.109 인용 PDF KSCI

Deformation Measurement of Accelerator Vacuum Chamber Using Optical Tooling Technique (광학기구기법을 이용한 가속기 진공챔버의 변형관측)

  • Kim, Byung Guk
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.3
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    • pp.181-194
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    • 1992

  • Deformations of a prototype vacuum chamber for the Storage Ring of the Pohang Light Source Project, due to both welding and baking, have been measured using the Optical Tooling Technique. The measurements aim for the acquisition of data for inspection of the chamber design and for the establishment of positional relationship with the components surrounding the chamber. The effectiveness of the Optical Tooling Technique, as a replacement for the conventional mechanical precision measurement, has been proved by the successful measurements of the vacuum chamber deformations.

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Comparisons of Measurement Methods of the Moisture Content of Dried Vegetables (건조채소(乾燥菜蔬)의 수분측정방법(水分測定方法) 비교(比較))

  • Kwon, C.S.;Lee, D.S.
    • Journal of Biosystems Engineering
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    • v.12 no.1
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    • pp.39-44
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    • 1987

  • Measurement methods of moisture content were compared with 7 dried vegetables (red pepper, onion, green onion, garlic, ginger, carrot and radish). The moisture contents of dried vegetables having different moisture contents were determined by atmospheric oven drying, infrared balance, vacuum oven and Karl Fisher methods. Vacuum oven and Karl Fisher methods gave the relatively agreed results and considered to give the accurate moisture content. Atmospheric oven drying and infrared balance methods resulted in higher moisture content than methods mentioned above, because of the thermal decomposition of solid. Calibration of the moisture data of atmospheric oven drying method into the vacuum oven data was undertaken. The thermodecomposable solid fraction was high in onion, radish, green onion and carrot, and was in the range of 8.0-11.7% of the total solid in these products.

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Uncooled Microbolometer FPA Sensor with Wafer-Level Vacuum Packaging (웨이퍼 레벨 진공 패키징 비냉각형 마이크로볼로미터 열화상 센서 개발)

  • Ahn, Misook;Han, Yong-Hee
    • Journal of Sensor Science and Technology
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    • v.27 no.5
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    • pp.300-305
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    • 2018

  • The uncooled microbolometer thermal sensor for low cost and mass volume was designed to target the new infrared market that includes smart device, automotive, energy management, and so on. The microbolometer sensor features 80x60 pixels low-resolution format and enables the use of wafer-level vacuum packaging (WLVP) technology. Read-out IC (ROIC) implements infrared signal detection and offset correction for fixed pattern noise (FPN) using an internal digital to analog convertor (DAC) value control function. A reliable WLVP thermal sensor was obtained with the design of lid wafer, the formation of Au80%wtSn20% eutectic solder, outgassing control and wafer to wafer bonding condition. The measurement of thermal conductance enables us to inspect the internal atmosphere condition of WLVP microbolometer sensor. The difference between the measurement value and design one is $3.6{\times}10-9$ [W/K] which indicates that thermal loss is mainly on account of floating legs. The mean time to failure (MTTF) of a WLVP thermal sensor is estimated to be about 10.2 years with a confidence level of 95 %. Reliability tests such as high temperature/low temperature, bump, vibration, etc. were also conducted. Devices were found to work properly after accelerated stress tests. A thermal camera with visible camera was developed. The thermal camera is available for non-contact temperature measurement providing an image that merged the thermal image and the visible image.

  • https://doi.org/10.5369/JSST.2018.27.5.300 인용 PDF KSCI