• Title/Summary/Keyword: In-situ density

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In-Situ Measurement of Chiller Performance and Thermal Storage Density of an Ice Thermal Storage System (빙축열 시스템 냉동기 성능 및 축열밀도 현장측정 기법연구)

  • Shin Younggy;Yang Hooncheul;Tae Choon-Seob;Cho Soo;Kim Youngil
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.12
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    • pp.1204-1209
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    • 2005
  • In-situ measurement was made to evaluate chiller performance and thermal storage density of an ice thermal storage system. The system belonged to a big hotel and the measurement was conducted during late October. Owing to very small cooling load, the data logging was possible for a single thermal storage cycle. However, operation history of the chiller showed a relatively good spectrum of data for performance evaluation. COP and thermal storage density were calculated. The COP at full load was about 4.07, which was lower than $4.8\~6.4$ of new chillers. The measured storage density was about $10.9RT-h/m^3\;(=152MJ/m^3)$, which also was lower than a criterion of normal performance $(above\;13.0RT-h/m^3\;or\;181MJ/m^3)$. The study result provides technical basis for quantitative ESCO business scenario.

Development of an Immobilized Adsorbent for In Situ Removal of Ammonium Ion from Animal Cell Culture Media and Its Applications to Animal Cell Culture System : II. Application to Cell Culture System (동물세포 배양액으로부터 암모늄 이온의 동시제거를 위한 고정화 흡착제의 개발과 동물세포 배양 시스템에의 응용 : II. 세포배양 시스템에의 응용)

  • 박병곤;이해익;전계택;김익환;정연호
    • KSBB Journal
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    • v.13 no.4
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    • pp.411-417
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    • 1998
  • The possibility of application of membrane type immobilized adsorbent to the fed-batch or perfusion culture system with anchorage-independent cells as well as batch system was investigated. The improvement in cell density and cell viability due to the combination of immobilized adsorbent with each culture system was evaluated for the investigation, and the optimum culture system employing immobilized adsorbent system was suggested based on the results. It was observed that the system with immobilized adsorbent showed better cell growth and cell viability than that without immobilized adsorbent in every operation system of batch, fed-batch, and perfusion. In case of batch system, 200% improvement of maximum cell density was observed in the system where ammonium chloride was added on purpose. And 50% improvement of maximum cell density was observed in the fed-batch system where ammonium ion accumulates significantly, while small increase in maximum cell density was observed in the perfusion system where dilution of waste byproducts exists. Especially, the fed-batch system showed the most significant improvement on cell growth because both compensation of nutrient and removal of ammonium ion occurred simultaneously in the system. Therefore a combined system of immobilized adsorbent and fed-batch operation could be suggested as an optimum system with in situ removal of ammonium ion.

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In-Situ Fluorine Passivation by Excimer Laser Annealing

  • Jung, Sang-Hoon;Kim, Cheon-Hong;Jeon, Jae-Hong;Yoo, Juhn-Suk;Han, Min-Koo
    • Journal of Information Display
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    • v.1 no.1
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    • pp.25-28
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    • 2000
  • We propose a new in-situ fluorine passivation of poly-Si TFTs using excimer laser annealing to reduce the trap state density and improve reliability significantly. To investigate the effect of an in-situ fluorine passivation, we have fabricated fluorine-passivated p-channel poly-Si TFTs and examined their electrical characteristics and stability. A new in-situ fluorine passivation brought about an improvement in electrical characteristic. Such improvement is due to the formation of stronger Si-F bonds than Si-H bonds in poly-Si channel and $SiO_2$/Poly-Si interface.

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In-Situ Application of the Steel Pipe jacking with Grouting (그라우팅을 병행한 강관추진공법의 현장 적용성 연구)

  • Jung, Min-Hyung;Lim, Ho-Jung;Shin, Chang-Sub;Lee, Song
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.13 no.1 s.53
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    • pp.152-160
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    • 2009
  • The pipe jacking method which is a non-excavation method is frequently used due to constructability and economical efficiency in a medium or small-sized pipeline construction. However, jacking process of the method still causes problems that the base ground is disturbed and loosen. These lead to surface settlement, strength decrease and leakage of water. Therefore, this study presents in-situ application of the steel pipe jacking with grouting, and it is that jacking and grouting are progressed simultaneously. To verify this, the steel pipe jacking with grouting and the existing steel pipe jacking have been constructed on the same ground condition. It has been proved that the steel pipe jacking with grouting is in-situ applicable according to results of monitoring surface settlement, in-situ density, GPR geophysical prospecting and large scale direct shear test.

Analysis of Effecting Parameters on Extraction of Soil Contaminants using Vertical Drains - Focusing on Soil and Contaminants Physical Properties (연직배수재에 의한 토양오염물질 추출에 미치는 영향인자 분석 - 토양 및 오염유체의 물성치를 중심으로)

  • Lee, Haeng-Woo;Chang, Pyoung-Wuck;Kang, Byung-Yoon;Kim, Hyun-Tae
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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    • pp.355-360
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    • 2005
  • The properties of contaminants, contaminated soil, and the elapsed time are important factors to in-situ soil remediation. Gabr et. al. (1996) derived the solution equation of contaminant concentration ratio as initial one $(C/C_0)$ with time and spatial changes in contaminated area with vertical drains. The contaminant concentration ratio $(C/C_0)$ is analyzed with time and spatial changes as varying the effective diameter, porosity, shape factor, density of contaminated soil and temperature in ground and unit weight, viscosity of contaminants by using FLUSH1 model. Results from numerical analysis indicate that the most important factor to the in-situ soil remediation using vertical drains is the effective diameter of contaminated soil. It also shows that the viscosity of contaminants, porosity of soil, shape of soil, temperature in ground, unit weight of contaminants are, in order, affected to the soil remediation but density of soil is insignificant to the soil remediation.

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A Study of Properties of GaN and LED Grown using In-situ SiN Mask (In-situ SiN 박막을 이용하여 성장한 GaN 박막 및 LED 소자 특성 연구)

  • Kim, Deok-Kyu;Yoo, In-Sung;Park, Choon-Bae
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.18 no.10
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    • pp.945-949
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    • 2005
  • We have grown GaN layers with in-situ SiN mask by metal organic chemical vapor deposition (MOCVD) and study the physical properties of the GaN layer. We have also fabricate PN junction light emitting diode (LED) to investigate the effect of the SiN mask on its optical property By inserting a SiN mask, (102) the full width at half maximum (FWHM) decreased from 480 arcsec to 409 arcsec and threading dislocation (TD) density decreased from $3.21{\times}10^9\;cm^{-2}$ to $9.7{\times}10^8\;cm^{-2}$. The output power of the LED with a SiN mask increased from 198 mcd to 392 mcd at 20 mA. We have thus shown that the SiN mask improved significantly the physical and optical properties of the GaN layer.

In-situ Fluorine Passivation by Excimer Laser Annealing

  • Jung, Sang-Hoon;Kim, Cheon-Hong;Jeon, Jae-Hong;Yoo, Juhn-Suk;Han, Min-Koo
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.155-156
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    • 2000
  • We propose a new in-situ fluorine passivation of poly-Si TFTs by excimer laser annealing to reduce the trap density and improve the reliability significantly. This improvement is due to the formation of stronger Si-F bonds than Si-H bonds which passivate the trap states.

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Analysis of Plants Shape by Image Processing (영상처리에 의한 식물체의 형상분석)

  • 이종환;노상하;류관희
    • Journal of Biosystems Engineering
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    • v.21 no.3
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    • pp.315-324
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    • 1996
  • This study was one of a series of studies on application of machine vision and image processing to extract the geometrical features of plants and to analyze plant growth. Several algorithms were developed to measure morphological properties of plants and describing the growth development of in-situ lettuce(Lactuca sativa L.). Canopy, centroid, leaf density and fractal dimension of plant were measured from a top viewed binary image. It was capable of identifying plants by a thinning top viewed image. Overlapping the thinning side viewed image with a side viewed binary image of plant was very effective to auto-detect meaningful nodes associated with canopy components such as stem, branch, petiole and leaf. And, plant height, stem diameter, number and angle of branches, and internode length and so on were analyzed by using meaningful nodes extracted from overlapped side viewed images. Canopy, leaf density and fractal dimension showed high relation with fresh weight or growth pattern of in-situ lettuces. It was concluded that machine vision system and image processing techniques are very useful in extracting geometrical features and monitoring plant growth, although interactive methods, for some applications, were required.

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The Characteristics of $GaAs_{0.35}P_{0.65}$ Epitaxial Layer According to in-situ doping of $NH_3$ gas (In-situ $NH_3$ doping에 따른 $GaAs_{0.35}P_{0.65}$ 에피막의 특성)

  • Lee, Eun-Cheol;Lee, Cheol-Jin
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1249-1251
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    • 1998
  • We have studied the properties of $GaAs_{0.35}P_{0.65}$ epitaxial films on the GaP according to doping of $NH_3$ gas using VPE method by CVD. The efficiency of $GaAs_{0.35}P_{0.65}$ epitaxial films found to be greatly enhanced by the according of nitrogen doping. The diodes were fabricated by means of Zn diffusion into vapor grown $GaAs_{0.35}P_{0.65}$ epitaxial films doped with N and Te. The effects of nitrogen doping on carrier density of epitaxial films, PL wavelength and the power out, forward voltage of diodes are discussed. In the end, The effect of electrical and optical properties is influenced by the deep level and deep level density of nitrogen doping.

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