• Title/Summary/Keyword: Thermal Spectrum

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Radical Addition Reaction of Phosphorous based Flame Retardant with End Groups of PET (2) - Reaction of Resorcinol bis(diphenyl phosphate) - (PET 말단에 대한 인계난연제의 라디칼계 부가반응 (2) - 리소시놀비스다이페닐포스페이트의 반응 -)

  • Kim, Min-Kwan;Sohn, Kwang-Ho;Ghim, Han-Do
    • Textile Coloration and Finishing
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    • v.24 no.1
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    • pp.39-44
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    • 2012
  • To improve flame retardation of poly(ethylene terephthalate) (PET) against burning, resorcinol bis(diphenyl phosphate) (RDP), phosphorous containing flame retardant, was incorporated into PET backbone by radical reaction pathway. Radical endcapping of PET with RDP was confirmed by spectroscopic and thermal analysis. From 400 MHz $^{31}P$ solid state FT-NMR spectrum of PET with RDP (PET-RDP), phosphorus spectra peak in RDP was found at ca. -10 ppm. Furthermore, P-C bond stretching vibration peaks were found ca. $530cm^{-1}$ in FT-IR spectrums of PET-RDP. These results indicated that RDP can be chemically bound at the ends of PET by radical addition method. Thermal characteristics of pure PET (pPET) and PET-RDP were measured and evaluated by TGA thermal analysis. There was not significant changes in thermal characteristics of PET-RDP compared to that of pPET.

Loss of Coolant Accident Analysis During Shutdown Operation of YGN Units 3/4

  • Bang, Young-Seok;Kim, Kap;Seul, Kwang-Won;Kim, Hho-Jung
    • Nuclear Engineering and Technology
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    • v.31 no.1
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    • pp.17-28
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    • 1999
  • A thermal-hydraulic analysis is conducted on the loss-of-coolant-accident (LOCA) during shutdown operation of YGN Units 3/4. Based on the review of plant-specific characteristics of YGN Units 3/4 in design and operation, a set of analysis cases is determined, and predicted by the RELAP5/MOD3.2 code during LOCA in the hot-standby mode. The evaluated thermal-hydraulic phenomena are blowdown, break flow, inventory distribution, natural circulation, and core thermal response. The difference in thermal-hydraulic behavior of LOCA at shutolown condition from that of LOCA at full power is identified as depressurization rate, the delay in peak natural circulation timing and the loop seal clearing (LSC) timing. In addition, the effect of high pressure safety injection (HPSI) on plant response is also evaluated. The break spectrum analysis shows that the critical break size can be between 1% to 2% of cold leg area, and that the available operator action time for the Sl actuation and the margin in the peak clad temperature (PCT) could be reduced when considering uncertainties of the present RELAP5 calculation.

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Design of an observer-based decentralized fuzzy controller for discrete-time interconnected fuzzy systems (얼굴영상과 예측한 열 적외선 텍스처의 융합에 의한 얼굴 인식)

  • Kong, Seong G.
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.5
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    • pp.437-443
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    • 2015
  • This paper presents face recognition based on the fusion of visible image and thermal infrared (IR) texture estimated from the face image in the visible spectrum. The proposed face recognition scheme uses a multi- layer neural network to estimate thermal texture from visible imagery. In the training process, a set of visible and thermal IR image pairs are used to determine the parameters of the neural network to learn a complex mapping from a visible image to its thermal texture in the low-dimensional feature space. The trained neural network estimates the principal components of the thermal texture corresponding to the input visible image. Extensive experiments on face recognition were performed using two popular face recognition algorithms, Eigenfaces and Fisherfaces for NIST/Equinox database for benchmarking. The fusion of visible image and thermal IR texture demonstrated improved face recognition accuracies over conventional face recognition in terms of receiver operating characteristics (ROC) as well as first matching performances.

Seismic Analysis of the Reflective Metal Insulation for Thermal Shielding of Main Equipments of Nuclear Power Plants (원전 설비 열차폐를 위한 반사형 금속단열재의 내진 해석)

  • Kim, Seung-Hyeon;Rhee, Huinam
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.6
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    • pp.166-172
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    • 2016
  • This paper deals with the seismic qualification of the reflective metal insulation for thermal shielding that is installed on the outer surfaces of the main equipment of the primary coolant system of a nuclear power plant. A small-scale model of the reactor pressure vessel, which has equivalent dynamic characteristics, was designed to be tested in domestic seismic testing facilities in the future. In this study, seismic analysis of the small-scale model installed with metal insulation was performed using equivalent static analysis and response spectrum analysis. The required Response Spectrum for main equipment of the primary coolant system of APR-1400 plant were considered to establish the enveloping response spectrum, which was applied to the seismic analysis model. The results from two seismic analysis methods were compared to show the structural adequacy of the metal insulator design against a safe shutdown earthquake. This study will form the basis for the seismic testing to support the seismic qualification of the reflective metal insulator.

Characteristics of glass-ceramics of LAS system having high thermal shock resistance and selective transparency in visible region of spectrum (가시광 스펙트럼 영역에서 선택적인 투과와 내열충격성을 갖는 LAS계 글라스세라믹의 특성)

  • Byun, W.B.
    • Proceedings of the KIEE Conference
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    • 2003.07c
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    • pp.1565-1567
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    • 2003
  • LAS($Li_2O-Al_2O_3-SiO_2$)계에 전이금속과 희토류 이온을 첨가한 글라스세라믹의 colouring에 대한 특성 분석이 이루어졌다. 투과성이 높고, 내열 충격성이 우수한 글라스세라믹을 제조한 수 있었으며, 주 결정상은 ${\beta}$-eucryptite(SS)이었다. 또한 colouring에 의한 빛의 흡수 특성과 이러한 글라스세라믹에서의 colouring 이온의 구조적 상태가 조사되었다.

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Effect of Niobium on the Electronic Properties of Passive Films on Zirconium Alloys

  • Kim, Bo Young;Kwon, Hyuk Sang
    • Corrosion Science and Technology
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    • v.2 no.2
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    • pp.68-74
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    • 2003
  • The effects of Niobium on the structure and properties(especially electric properties) of passive film of Zirconium alloys in pH 8.5 buffer solution are examined by the photo-electrochemical analysis. For Zr-xNb alloys (x = 0, 0.45, 1.5, 2.5 wt%), photocurrent began to increase at the incident energy of 3.5 ~ 3.7 eV and exhibited the $1^{st}$ peak at 4.3 eV and the $2^{nd}$ peak at 5.7 eV. From $(i_{ph}hv)^{1/2}$ vs. hv plot, indirect band gap energies $E_g{^1}$= 3.01~3.47 eV, $E_g{^2}$= 4.44~4.91 eV were obtained. With increasing Nb content, the relative photocurrent intensity of $1^{st}$ peak significantly increased. Compared with photocurrent spectrum of thermal oxide of Zr-2.5Nb, It was revealed that $1^{st}$ peak in photocurrent spectrum for the passive film formed on Zr-Nb alloy was generated by two types of electron transitions; the one caused by hydrous $ZrO_2$ and the other created by Nb. Two electron transition sources were overlapped over the same range of incident photon energy. In the photocurrent spectrum for passive film formed on Zr-2.5Nb alloy in which Nb is dissolved into matrix by quenching, the relative photocurrent intensity of $1^{st}$ peak increased, which implies that dissolved Nb act as another electron transition source.

Review on the Solar Fuel Production Technology Using High-Temperature Solar Furnace (초고온 태양열을 이용한 태양연료 생산기술 연구동향)

  • Kang Yong-Heack;Kim Jin-Soo;Lee Sang-Nam;Yoon Hwan-Ki;Yu Chang-Kyun
    • 한국신재생에너지학회:학술대회논문집
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    • 2005.06a
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    • pp.408-411
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    • 2005
  • Solar fuel production technology using high-temperature solar furnace was briefly reviewed in this paper. 'Hydrogen' which is known to be the most promising energy carrier in the near future is to be generated environment-friendly from non-carbon resources. Combination of solar furnace operated by concentrated solar energy and high-temperature thermal reactions could be one of the most efficient ways to fulfill this need eventually. Various reaction mechanisms are feasible within a wide spectrum of solar fuel production technology, but intensive research efforts in related key areas need to be taken for successful development and commercialization of the technology.

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A study on the Drying Characteristics of NIR Dryer (근 적외선 건조기의 건조특성에 대한 연구)

  • Jang, Yeong-Suk
    • Journal of the Korean Solar Energy Society
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    • v.24 no.1
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    • pp.21-27
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    • 2004
  • Near Infrared Ray (NIR) are primarily of interest to the high energy physicist. It is the intermediate portion of the spectrum, which extends from approximately 0.8 to 1.5 ${\mu}m$ and include a portion of the all of infrared, that is thermal radiation and is pertinent to heat transfer. It is important to study that temperature distribution of the drying materials by surface encompasses a range of NIR wave lengths. This study is to investigate the characteristics of NIR dryer by experimental results. it was made a comparison with various textiles, velocity ratio and distance of lamp and textiles. In case of spongy type textile the drying performance is the superior of all. The 0.15m distance drying effect of improvement 30% more than 0.26m distance between lamp and textiles. As the contained water increases, the drying speed for textile can be increased.

Improvement of Luminance Properties of Blue OLEO using $SnDP(HPB)_2$ (Sn-complexes를 이용한 OLED의 발광 특성 향상에 관한 연구)

  • Kim, Dong-Eun;Choi, Gyu-Chae;Kwon, Young-Soo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.04c
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    • pp.121-122
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    • 2008
  • Blue emitting materials have been explored by various researchers. However, blue-emitting materials with high luminous efficiency, good color purity, and thermal stability are still much desired. In this study, we synthesized a new blue luminescent material, $SnDP(HPB)_2$ which is low molecular compound and thermal stability. The PL spectrum of $SnDP(HPB)_2$ was observed blue at the wavelength of 447nm. The ionization potential(IP) and the electron affinity(EA) of $SnDP(HPB)_2$ was measured to be 6.7 eV and 3.0 eV, respectively. The fundamental structure of the OLED was ITO/NPB/$SnDP(HPB)_2/Alq_3$/LiF/Al. As a Result, we obtained to enhance the performance of blue OLED.

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Degradation Estimation Of Material by Barkhausen Noise Analysis (바크하우젠 노이즈 해석에 의한 재료의 열화도 평가)

  • Lee Myung Ho
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.14 no.3
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    • pp.38-46
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    • 2005
  • The destructive method is reliable and widely used for the estimation of material degradation but it have time-consuming and a great difficulty in preparing specimens from in-service industrial facilities. Therefore, the estimation of degraded structural materials used at high temperature by nondestructive evaluation such as electric resistance method, replica method, Barkhausen noise method, electro-chemical method and ultrasonic method are strongly desired. In this study, various nondestructive evaluation(NDE) parameters of the Barkhausen noise method, such as MPA(Maximum Peak Amplitude), RMS, IABNS(Internal Area of Barkhausen Noise on Signal) and average amplitude of frequency spectrum are investigated and correlated with thermal damage level of 2.25cr-1.0Mo steel using wavelet analysis. Those parameters tend to increase while thermal degradation proceeds. It also turns out that the wavelet technique can help to reduce experimental false call in data analysis.