• 제목/요약/키워드: conjugate addition

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계층적 기저함수와 다해상도 영상을 이용한 영사응로부터 물체의 형상복구 (Shape from Shading using the Hierarchical basis Function and Multiresolution Images)

  • 이승배;이상욱;최종수
    • 전자공학회논문지B
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    • 제29B권11호
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    • pp.73-84
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    • 1992
  • In this paper, an algorithm for recovering the 3-D shape from a single shaded image is proposed. In the proposed algorithm, by using the relation between the height and surface gradient (p, q), a set of linear equations is derived from the linearized reflectance function. Then the 3-D surface is recovered by employing the conjugate gradient technique. In order to improve the convergence speed of the solution, we also employ the hierarchical basis function and multiresolution images in the algorithm. A method for determining the regularization parameter, which is determined by trial and error in the conventional approach, is also introduced. In addition, the proposed algorithm attempts to recover the 3-D surface without requiring the boundary conditions, making it suitable for a real-time implementation. Simulation results for real image as well as synthetic image are provided to demonstrate the performance of the proposed algorithm.

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Response and transcriptional regulation of rice SUMOylation system during development and stress conditions

  • Chaikam, Vijay;Karlson, Dale T.
    • BMB Reports
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    • 제43권2호
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    • pp.103-109
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    • 2010
  • Modification of proteins by the reversible covalent addition of the small ubiquitin like modifier (SUMO) protein has important consequences affecting target protein stability, sub-cellular localization, and protein-protein interactions. SUMOylation involves a cascade of enzymatic reactions, which resembles the process of ubiquitination. In this study, we characterized the SUMOylation system from an important crop plant, rice, and show that it responds to cold, salt and ABA stress conditions on a protein level via the accumulation of SUMOylated proteins. We also characterized the transcriptional regulation of individual SUMOylation cascade components during stress and development. During stress conditions, majority of the SUMO cascade components are transcriptionally down regulated. SUMO conjugate proteins and SUMO cascade component transcripts accumulated differentially in various tissues during plant development with highest levels in reproductive tissues. Taken together, these data suggest a role for SUMOylation in rice development and stress responses.

Adjustment of Exterior Orientation of the Digital Aerial Images using LiDAR Points

  • Yoon, Jong-Suk
    • 한국측량학회지
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    • 제26권5호
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    • pp.485-491
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    • 2008
  • LiDAR systems are usually incorporated a laser scanner and GPS/INS modules with a digital aerial camera. LiDAR point clouds and digital aerial images acquired by the systems provide complementary spatial information on the ground. In addition, some of laser scanners provide intensity, radiometric information on the surface of the earth. Since the intensity is unnecessary of registration and provides the radiometric information at a certain wavelength on the location of LiDAR point, it can be a valuable ancillary information but it does not deliver sufficient radiometric information compared with digital images. This study utilize the LiDAR points as ground control points (GCPs) to adjust exterior orientations(EOs) of the stereo images. It is difficult to find exact point of LiDAR corresponding to conjugate points in stereo images, but this study used intensity of LiDAR as an ancillary data to find the GCPs. The LiDAR points were successfully used to adjust EOs of stereo aerial images, therefore, successfully provided the prerequisite for the precise registration of the two data sets from the LiDAR systems.

A New Dual Hardy-Hilbert's Inequality with some Parameters and its Reverse

  • Zhong, Wuyi
    • Kyungpook Mathematical Journal
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    • 제49권3호
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    • pp.493-506
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    • 2009
  • By using the improved Euler-Maclaurin summation formula and estimating the weight coefficients in this paper, a new dual Hardy-Hilbert's inequality and its reverse form are obtained, which are all with two pairs of conjugate exponents (p, q); (r, s) and a independent parameter ${\lambda}$. In addition, some equivalent forms of the inequalities are considered. We also prove that the constant factors in the new inequalities are all the best possible. As a particular case of our results, we obtain the reverse form of a famous Hardy-Hilbert's inequality.

AN ITERATIVE ALGORITHM FOR THE LEAST SQUARES SOLUTIONS OF MATRIX EQUATIONS OVER SYMMETRIC ARROWHEAD MATRICES

  • Ali Beik, Fatemeh Panjeh;Salkuyeh, Davod Khojasteh
    • 대한수학회지
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    • 제52권2호
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    • pp.349-372
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    • 2015
  • This paper concerns with exploiting an oblique projection technique to solve a general class of large and sparse least squares problem over symmetric arrowhead matrices. As a matter of fact, we develop the conjugate gradient least squares (CGLS) algorithm to obtain the minimum norm symmetric arrowhead least squares solution of the general coupled matrix equations. Furthermore, an approach is offered for computing the optimal approximate symmetric arrowhead solution of the mentioned least squares problem corresponding to a given arbitrary matrix group. In addition, the minimization property of the proposed algorithm is established by utilizing the feature of approximate solutions derived by the projection method. Finally, some numerical experiments are examined which reveal the applicability and feasibility of the handled algorithm.

선 배열에서 표적체의 방위 모호성과 분해능 향상을 위한 신호처리 기법 (Signal Processing for Improvement of Resolution and Direction Ambiguity of Source in Line Array)

  • 손윤준;천승용;김기만
    • 한국음향학회지
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    • 제22권6호
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    • pp.482-488
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    • 2003
  • 선 배열을 이용한 빔 형성시 특정 지향 방향을 기준으로 반대 방향에 동일한 이득을 갖게 되어 수신단에서는 좌/우측 방위구분에 있어 모호성을 갖는다 이에 본 논문에서는 선 배열에 카디오이드 빔을 적용하여 좌/우측 방위 구분의 모호성을 해결하고, 아울러 어레이 합성 처리 기법을 사용하여 음원에 대한 공간적 데이터 수를 증가시키고 음원으로부터 얻은 정보를 코히어런트 합성 처리함으로써 배열 센서가 갖는 공간적인 분해능의 한계를 극복하였다. 시뮬레이션 결과에서는 좌/우측 방위 구분에 대한 성능을 어레이 합성 횟수에 따라 나타내었다.

Effect of Amine Nature on Rates and Mechanism: Pyridinolyses of 4-Nitrophenyl Benzoate

  • Um, Ik-Hwan;Baek, Mi-Hwa;Han, Hyun-Joo
    • Bulletin of the Korean Chemical Society
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    • 제24권9호
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    • pp.1245-1250
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    • 2003
  • Pseudo-first-order rate constants ($k_{obs}$) have been measured spectrophotometrically for the reactions of 4-nitrophenyl benzoate with a series of pyridines in $H_2O$ containing 20 mol % DMSO. The plots of kobs vs pyridine concentration are linear up to ca. 0.1 M pyridines, indicating that the effect of self-association of pyridines with their conjugate acids are insignificant in this concentration range. The Bronsted-type plot has been obtained to be linear with a ${\beta}_{nuc}$ value 1.11, suggesting that the pyridinolyses proceed through a rate-determining breakdown of the zwiterionic addition intermediate. The pyridines studied have shown higher reactivity than isobasic primary and secondary amines toward the substrate. 1-Benzoyl-4-dimethylaminopyridinium ion, a possible intermediate, has not been detected since the rate of its hydrolysis in the reaction condition is comparable with or even faster than its formation.

Regioselective Synthesis of Heterocyclic Ketene N,N-, N,O- and N,S-acetals in Aqueous Medium

  • Chanu, Langpoklakpam Gellina;Singh, Okram Mukherjee;Jang, Sang-Hun;Lee, Sang-Gyeong
    • Bulletin of the Korean Chemical Society
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    • 제31권4호
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    • pp.859-862
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    • 2010
  • The reactions of ketene dithioacetals with ethane-1,2-diamine, propane-1,3-diamine, 2-aminoethanol, 3-aminopropanol, and 2-aminoethanethiol in ordinary water in the absence of any acid/base catalyst afforded the heterocyclic ketene N,N-, N,O- and N,S-acetals in good yields.

Hydroiminoacylation of $\alpha,\omega$-diene with Aldimine by Rh(Ⅰ) and Isomerization of the Terminal Olefin to the Internal Olefin

  • Jun, Chul-Ho;Kang, Jung-Bu;Lim, Yeong-Gweon
    • Bulletin of the Korean Chemical Society
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    • 제14권2호
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    • pp.287-291
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    • 1993
  • Catalytic iminohydroacylation has been achieved by the reaction of aldimine 1 and 1,5-hexadiene (2a) with Wilkinson's complex as catalyst. Compounds 7a, 8a and 9a were obtained as final product after hydrolysis of the resulting iminohydroacylation products 4a, 5a and 6a. Depending on the reactant ratio (2/1), the ratio of products were changed dramatically : As the 2/1 ratio was increased, 7a is the major product after hydrolysis while 8a is the major with an 1/1 ratio of 2/1. The mechanism of the formation of 5a is determined by the reaction of 1 and 2b under the identical reaction conditions. Considering that 5a may not be formed from the hydroiminoacylation of 14a since 5b cannot be formed from that of conjugate diene 14b generated from isomerization of 2b, 5a must be formed from the reaction of 4a and 10 by addition-elimination mechanism.

Corona-Cov-2 (COVID-19) and ginseng: Comparison of possible use in COVID-19 and influenza

  • Lee, Won Sik;Rhee, Dong-Kwon
    • Journal of Ginseng Research
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    • 제45권4호
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    • pp.535-537
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    • 2021
  • In the 1918 influenza pandemic, more than 95% of mortalities were ascribed to bacterial pneumonia. After the primary influenza infection, the innate immune system is attenuated, and the susceptibility to bacteria is increased. Subsequent bacterial pneumonia exacerbates morbidity and increases the mortality rate. Similarly, COVID-19 infection attenuates innate immunity and results in pneumonia. In addition, the current pneumococcal conjugate vaccine may have limited defense against secondary pneumococcal infection after influenza infection. Therefore, until a fully protective vaccine is available, a method of increasing immunity may be helpful. Ginseng has been shown to increase the defense against influenza in clinical trials and animal experiments, as well as the defense against pneumococcal pneumonia in animal experiments. Based on these findings, ginseng is suspected to be helpful for providing immunity against COVID-19.