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  • 1
    Electronic Resource
    Electronic Resource
    R and D Project Selection and Evaluation: A Microcomputer-Based Approach (1987)
    Oxford, UK : Blackwell Publishing Ltd
    R & D management 17 (1987), S. 0 
    Details
    ISSN: 1467-9310
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Economics
    Notes: This paper develops microcomputer-based R and D project selection and project evaluation models. The models use Lotus 1-2-3 as a vehicle to provide practical research management support suitable for a developing country. The models are readily adaptable for various R and D management applications.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1467-9310.1987.tb00062.x
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  • 2
    Electronic Resource
    Electronic Resource
    The theory of electrostatic potential in superconductors (2004)
    Springer
    The European physical journal 37 (2004), S. 489-498 
    Details
    ISSN: 1434-6036
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract. The problem of electrostatic potential distribution in superconductors is studied based on the microscopic theory of superconductors. Local chemical potential of the superconductor is introduced, and an approximation is made to BG theory, which is similar to the Thomas-Fermi (TF) method used in quantum mechanics. The electrostatic potential and charge distribution around an isolated vortex in type-II superconductors is discussed within the approximation. A correction to GL theory considering the electrostatic potential distribution is suggested.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1140/epjb/e2004-00085-1
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  • 3
    Electronic Resource
    Electronic Resource
    Circulant preconditioners for second order hyperbolic equations (1992)
    Springer
    BIT 32 (1992), S. 650-664 
    Details
    ISSN: 1572-9125
    Keywords: 65F10 ; 65N22 ; Hyperbolic equation ; circulant matrix ; condition number ; preconditioned conjugate gradient method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract Linear systems arising from implicit time discretizations and finite difference space discretizations of second-order hyperbolic equations in two dimensions are considered. We propose and analyze the use of circulant preconditioners for the solution of linear systems via preconditioned iterative methods such as the conjugate gradient method. Our motivation is to exploit the fast inversion of circulant systems with the Fast Fourier Transform (FFT). For second-order hyperbolic equations with initial and Dirichlet boundary conditions, we prove that the condition number of the preconditioned system is ofO(α) orO(m), where α is the quotient between the time and space steps andm is the number of interior gridpoints in each direction. The results are extended to parabolic equations. Numerical experiments also indicate that the preconditioned systems exhibit favorable clustering of eigenvalues that leads to a fast convergence rate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01994848
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  • 4
    Electronic Resource
    Electronic Resource
    A preconditioner for constrained and weighted least squares problems with Toeplitz structure (1996)
    Springer
    BIT 36 (1996), S. 101-109 
    Details
    ISSN: 1572-9125
    Keywords: Toeplitz matrix ; circulant matrix ; least squares ; PCG method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We study methods for solving the constrained and weighted least squares problem min x $$\min _x \tfrac{1}{2}\left( {b - Ax} \right)^T W\left( {b - Ax} \right)$$ by the preconditioned conjugate gradient (PCG) method. HereW = diag (ω1, ⋯, ω m ) with ω1 ≥ ⋯ ≥ ω m ≥ 0, andA T = [T 1 T , ⋯,T k T ] with Toeplitz blocksT l εR n × n ,l = 1, ⋯,k. It is well-known that this problem can be solved by solving anaugmented linear 2 × 2 block linear systemMλ +Ax =b, A T λ = 0, whereM =W −1. We will use the PCG method with circulant-like preconditioner for solving the system. We show that the spectrum of the preconditioned matrix is clustered around one. When the PCG method is applied to solve the system, we can expect a fast convergence rate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01740547
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  • 5
    Electronic Resource
    Electronic Resource
    Circulant and skew-circulant preconditioners for skew-hermitian type Toeplitz systems (1991)
    Springer
    BIT 31 (1991), S. 632-646 
    Details
    ISSN: 1572-9125
    Keywords: 65F10 ; 65F15 ; Skew-Hermitian type Toeplitz matrix ; circulant matrix ; skew-circulant matrix ; preconditioned conjugate gradient method
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract We study the solutions of Toeplitz systemsA n x=b by the preconditioned conjugate gradient method. Then ×n matrixA n is of the forma 0 I+H n wherea 0 is a real number,I is the identity matrix andH n is a skew-Hermitian Toeplitz matrix. Such matrices often appear in solving discretized hyperbolic differential equations. The preconditioners we considered here are the circulant matrixC n and the skew-circulant matrixS n whereA n =1/2(C n +S n ). The convergence rate of the iterative method depends on the distribution of the singular values of the matricesC −1 n An andS −1 n A n . For Toeplitz matricesA n with entries which are Fourier coefficients of functions in the Wiener class, we show the invertibility ofC n andS n and prove that the singular values ofC −1 n A n andS −1 n A n are clustered around 1 for largen. Hence, if the conjugate gradient method is applied to solve the preconditioned systems, we expect fast convergence.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01933178
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  • 6
    Electronic Resource
    Electronic Resource
    Circulant integral operators as preconditioners for Wiener-Hopf equations (1995)
    Springer
    Integral equations and operator theory 21 (1995), S. 12-23 
    Details
    ISSN: 1420-8989
    Keywords: 45E10 ; 45L10 ; 65R20 ; 65J10
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mathematics
    Notes: Abstract In this paper, we study the solutions of finite-section Wiener-Hopf equations by the preconditioned conjugate gradient method. Our main aim is to give an easy and general scheme of constructing good circulant integral operators as preconditioners for such equations. The circulant integral operators are constructed from sequences of conjugate symmetric functions {C τ}τ. Letk(t) denote the kernel function of the Wiener-Hopf equation and $$\hat k(t)$$ be its Fourier transform. We prove that for sufficiently large τ if {C τ}τ is uniformly bounded on the real lineR and the convolution product of the Fourier transform ofC τ with $$\hat k(t)$$ uniformly onR, then the circulant preconditioned Wiener-Hopf operator will have a clustered spectrum. It follows that the conjugate gradient method, when applied to solving the preconditioned operator equation, converges superlinearly. Several circulant integral operators possessing the clustering and fast convergence properties are constructed explicitly. Numerical examples are also given to demonstrate the performance of different circulant integral operators as preconditioners for Wiener-Hopf operators.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01262989
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  • 7
    Electronic Resource
    Electronic Resource
    Citations and scientific progress: Comparing bibliometric measures with scientist judgments (1988)
    Springer
    Scientometrics 13 (1988), S. 103-124 
    Details
    ISSN: 1588-2861
    Source: Springer Online Journal Archives 1860-2000
    Topics: Information Science and Librarianship , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Abstract This project compares various bibliometric measures and scientists' own judgments. Publication and cittion data are compiled for two cohorts of chemists awarded Sloan Fellowships. Citation patterns differ substantially between most cited papers and those these authors identify as their “best.” Theoretical, empirical, and methodological papers are contrasted as well. In addition, temporal citation patterns show that recognition spreads beyond the research area of a particular paper to yield “cross-disciplinary” citation surprisingly rapidly. Results suggest the utility of studying citation patterns among the Institute for Scientific Information Subject Categories, but also caution against equating publication and citation counts with scientific progress.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02017178
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  • 8
    Electronic Resource
    Electronic Resource
    A study of the residual microstress at the matrix interface in filled epoxy resins (1992)
    Stamford, Conn. [u.a.] : Wiley-Blackwell
    Polymer Engineering and Science 32 (1992), S. 678-685 
    Details
    ISSN: 0032-3888
    Keywords: Chemistry ; Chemical Engineering
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Using the technique of photoelasticity, we have studied in detail the magnitude of the residual microstress at the matrix interface between epoxy resin and rubber particles or glass beads. A spheric stress-optic equation applicable to these composites was derived. The photoelastic figures induced by the interfacial residual microstresses and the factors affecting the intensity of light are discussed. The experimental results show that the residual microstresses at the matrix interface are independent of the particle size of rubbers or glass beads, but depend on the nature of fillers, which have different thermal expansion coefficients and mechanical properties. Thermal history and interfacial chemical bonding of filled epoxy resins have distinct effects on the residual interfacial microstresses and the matrix internal stresses.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pen.760321006
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  • 9
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    Finite size scaling study ofNf=4finite density QCD on the lattice (2013)
    American Physical Society
    Details
    Publication Date: 2013-11-22
    Print ISSN: 1550-7998
    Electronic ISSN: 1550-2368
    Topics: Physics
    Published by American Physical Society
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  • 10
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    Curvature of the critical line on the plane of quark chemical potential and pseudoscalar meson mass for three-flavor QCD (2015)
    American Physical Society
    Details
    Publication Date: 2015-12-22
    Print ISSN: 1550-7998
    Electronic ISSN: 1550-2368
    Topics: Physics
    Published by American Physical Society
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