• Title/Summary/Keyword: NUC

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New Non-uniformity Correction Approach for Infrared Focal Plane Arrays Imaging

  • Qu, Hui-Ming;Gong, Jing-Tan;Huang, Yuan;Chen, Qian
    • Journal of the Optical Society of Korea
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    • v.17 no.2
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    • pp.213-218
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    • 2013
  • Although infrared focal plane array (IRFPA) detectors have been commonly used, non-uniformity correction (NUC) remains an important problem in the infrared imaging realm. Non-uniformity severely degrades image quality and affects radiometric accuracy in infrared imaging applications. Residual non-uniformity (RNU) significantly affects the detection range of infrared surveillance and reconnaissance systems. More effort should be exerted to improve IRFPA uniformity. A novel NUC method that considers the surrounding temperature variation compensation is proposed based on the binary nonlinear non-uniformity theory model. The implementing procedure is described in detail. This approach simultaneously corrects response nonlinearity and compensates for the influence of surrounding temperature shift. Both qualitative evaluation and quantitative test comparison are performed among several correction technologies. The experimental result shows that the residual non-uniformity, which is corrected by the proposed method, is steady at approximately 0.02 percentage points within the target temperature range of 283 K to 373 K. Real-time imaging shows that the proposed method improves image quality better than traditional techniques.

Detection of Methicillin Resistance in Staphylococcus aureus Isolates Using Two-Step Triplex PCR and Conventional Methods

  • Cho, Joon-Il;Jung, Hye-Jin;Kim, Young-Joon;Park, Sung-Hee;Ha, Sang-Do;Kim, Keun-Sung
    • Journal of Microbiology and Biotechnology
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    • v.17 no.4
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    • pp.673-676
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    • 2007
  • A two-step triplex PCR assay targeting the mecA, femA, and nuc genes was developed for the detection of methicillin resistance genes harbored by some Staphylococcus aureus isolates and for the simultaneous identification of such isolates at the species level. The triplex PCR revealed the presence of the femA and nuc genes in all the S. aureus isolates examined (n=105). Forty-four clinical isolates were mecA positive and no foodborne isolates were mecA positive. The PCR results had a 98 or 99% correlation with the results of PBP2a latex agglutination tests or oxacillin susceptibility tests, respectively.

Favorable effect of corticosteroids in treating acute-on-chronic liver failure underlying chronic hepatitis B

  • Kim, Hyeji;Kwon, Jung Hyun;Kim, Yong Hee;Nam, Soon Woo;Lee, Jong Yul;Jang, Jeong Won
    • Clinical and Molecular Hepatology
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    • v.24 no.4
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    • pp.430-435
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    • 2018
  • Acute-on-chronic liver failure (ACLF) occurs in the presence of a chronic liver disease or cirrhosis, and often results from exacerbation of chronic hepatitis B (CHB). The efficacy of corticosteroid treatment in ACLF patients with underlying CHB remains unclear. We report the case of a 50-year-old woman who experienced ACLF due to CHB exacerbation and was treated with a combination of corticosteroids and nucleot(s)ide analogue (NUC). The patient showed rapid decompensation due to CHB exacerbation. Three months of antiviral therapy produced no improvement in liver function. Combination therapy with corticosteroids and NUC was started, which did result in improvement of liver function. This case shows that the combined therapy of corticosteroids and NUC can be effective in treating ACLF due to CHB exacerbation.

Non Uniformity Error of MSC (Multi Spectral Camera) System

  • Jang YoungJun;Yong SangSoon;Kang KeumSil;Kim JungAh;Kang SungDuk;Youn HeongSik
    • Proceedings of the KSRS Conference
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    • 2004.10a
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    • pp.432-435
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    • 2004
  • MSC (Multi Spectral Camera) system is a remote sensing payload to obtain high resolution ground image. In this application, uniformity characteristic is important as well as GSD (Ground Resolved Distance) and SNR (Signal to Noise Ratio). MSC image chain is consisted of OM (Optical Module), CCD, Video processor, NUC and DCSU (Data Compression and Storage Unit). Each block makes and corrects MSC's nonuniformity response. This paper shows the cause of nonuniformity error and the correction scheme of MSC system from the electronic point of view.

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Design of a Reorganization and Non-Uniformity Correction Module for CCD Pixels in MSC(Multispectral Camera)

  • Kong, Jon-Pil;Yong, Sang-Soon;Heo, Haeng-Pal;Kim, Young-Sun;Paik, Hong-Yul
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.177.1-177
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    • 2001
  • This paper describes the design of a NUC(Non-uniformity Correction) module in MSC(Multispectral Camera) which will be a payload on KOMPSAT. This module is required inside a system with data compression module like MSC to minimize the loss of imagery due to non-uniform characteristics between CCD pixels when the imagery is received and processed on a ground station. It comprises Hotlink input/output for imagery data, RS-422 interface with main controller in MSC, a number of SRAMS for storing imagery data and parameters, FPGA controllers which control the entire NUC module under the control of main controller, etc. It inputs 8-channel imagery pixel data which consist of 2-channel MS(Multispectral) band and ...

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The magnitude of ${\rho}x({\rho}_{nuc})$ versus the extent of bond formation in $S_N2$ Reactions

  • Lee, Ik-Choon;Koh, Han-Joong;Lee, Byung-Choon;Park, Byong-Seo
    • Bulletin of the Korean Chemical Society
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    • v.15 no.7
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    • pp.576-581
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    • 1994
  • The secondary deuterium kinetic isotope effects (SDKIE) involving deuterated aniline nucleophiles are reported for the reactions of benzyl bromides and chlorides and benzoyl chlorides in acetonitrile. The benzyl systems behave normally as to the trend of changes in SDKIE with the magnitude of ${\rho}X({\rho}_{nuc})$, whereas benzoyl system shows ananomaly; ${\mid}{\rho}_X{\mid}$ decreases with increase in the extent of bond making estimated by the SDKIE. This has been ascribed to the negative charge accumulation at the reaction center carbon in the transition state. The magnitude of ${\rho}_{XY}$ is found to decrease by ca. 0.03 with ten degree rise in the reaction temperature.

A Kinetic Study on Aminolysis of t-Butyl 4-Pyridyl Carbonate and Related Compounds: Effect of Leaving and Nonleaving Groups on Reaction Mechanism

  • Kang, Ji-Sun;Lee, Jae-In;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.33 no.9
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    • pp.2971-2975
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    • 2012
  • Second-order rate constants $k_N$ have been measured spectrophotometrically for nucleophilic substitution reactions of t-butyl 4-pyridyl carbonate 8 with a series of alicyclic secondary amines in $H_2O$ at $25.0{\pm}0.1^{\circ}C$. The Br${\emptyset}$nsted-type plot for the reactions of 8 is linear with ${\beta}_{nuc}$ = 0.84. The ${\beta}_{nuc}$ value obtained for the reactions of 8 is much larger than that reported for the corresponding reactions of t-butyl 2-pyridyl carbonate 6 (i.e., ${\beta}_{nuc}$ = 0.44), which was proposed to proceed through a forced concerted mechanism. Thus, the aminolysis of 8 has been concluded to proceed through a stepwise mechanism with a zwitterionic tetrahedral intermediate $T^{\pm}$, in which expulsion of the leaving-group from $T^{\pm}$ occurs at the rate-determining step (RDS). In contrast, aminolysis of benzyl 4-pyridyl carbonate 7 has been reported to proceed through two intermediates, $T^{\pm}$ and its deprotonated form $T^-$ on the basis of the fact that the plots of pseudo-first-order rate constant $k_{obsd}$ vs. amine concentration curve upward. The current study has demonstrated convincingly that the nature of the leaving and nonleaving groups governs the reaction mechanism. The contrasting reaction mechanisms have been rationalized in terms of an intramolecular H-bonding interaction, steric acceleration, and steric inhibition.

Black Body Design and Verification for Non-Uniformity Correction of Imaging Sensor and Uncertainty Analysis (영상센서의 비균일 응답특성 보정을 위한 흑체 설계 및 성능검증과 보정오차 분석)

  • Shin, Somin
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.41 no.3
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    • pp.240-245
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    • 2013
  • Each pixel of InfraRed(IR) sensor differently responds to IR light as time elapses or the sensor on/off operation is repeated. As a result, the quality of IR sensor image is deteriorated, and therefore NUC(Non-uniformity Correction) is periodically needed for IR sensor. In this paper, in order to perform NUC in the Satellite, on-board V-grooved blackbody is designed with a baffle so that the emissivity of black body is to be higher than 0.995 as well as the temperature deviation is less than $1^{\circ}C$ in the range of the infrared wave length from 3.3 to $5.2{\mu}m$. To check its performance, the emissivity and the surface temperature of the blackbody by TRT(Transfer Reference Thermometer) and IR Micrometer scanner are measured, respectively. From the results, black body design is verified and the uncertainty of NUC is estimated through the measurement results.

Kinetic Study on Aminolysis of 4-Pyridyl X-Substituted Benzoates: Effect of Substituent X on Reactivity and Reaction Mechanism

  • Lee, Jong-Pal;Bae, Ae-Ri;Um, Ik-Hwan
    • Bulletin of the Korean Chemical Society
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    • v.32 no.6
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    • pp.1907-1911
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    • 2011
  • A kinetic study is reported for nucleophilic substitution reactions of 4-pyridyl X-substituted benzoates 7a-e with a series of alicyclic secondary amines in H2O. The Br${\o}$nsted-type plot for the reactions of 4-pyridyl benzoate 7c is linear with ${\beta}_{nuc}$ = 0.71. The corresponding reactions of 2-pyridyl benzoate 6, which is less reactive than 7c, resulted in also a linear Br${\o}$nsted-type plot with ${\beta}_{nuc}$ = 0.77. The fact that the more reactive 7c results in a smaller ${\beta}_{nuc}$ value appears to be in accord with the reactivity-selectivity principle. The aminolysis of 7c has been suggested to proceed through a stepwise mechanism in which breakdown of the intermediate is the rate-determining step (RDS). The Hammett plot for the reactions of 7a-e with piperidine consists of two intersecting straight lines, i.e., ${\rho}_X$ = 1.47 for substrates possessing an electron-donating group (EDG) and ${\rho}_X$ = 0.91 for those possessing an electron-withdrawing group (EWG). In contrast, the corresponding Yukawa-Tsuno plot exhibits excellent linear correlation with ${\rho}_X$ = 0.79 and r = 0.56. Thus, it has been concluded that the nonlinear Hammett plot is not due to a change in the RDS but is caused by stabilization of the ground state of the substrates possessing an EDG through resonance interaction between the EDG and the C=O bond of the substrates.