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Showing 1 to 20 of 28 for “"Wiener-Hopf"”.
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A Technique for Solving Certain Wiener-Hopf Type Boundary Value Problems
Made available in DSpace on 2014-12-08T22:23:58Z (GMT). No. of bitstreams: 1 6612288.pdf: 3011333 bytes, checksum: 83127792f8c85c7535684ed710a87216 (MD5) Previous issue date: 1966
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On the Factorisation of Matrix Wiener–Hopf Kernels Arising From Acoustic Scattering Problems
… that these problems may be formulated as matrix Wiener–Hopf problems with the special property that their matrix kernels $\mathsf K$ may be formulated as $\mathsf K = \mathsf M^{-1} \mathsf J \mathsf M$, where $\mathsf J^2 = \mathsf I$, the identity matrix. This special property makes the …
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Boundary value and Wiener-Hopf problems for abstract kinetic equations with nonregular collision operators
… decomposition of H which is equivalent to a Wiener-Hopf factorization. The accretivity of A is crucial in this step. When A is of the form "identity plus a compact operator", we work in the original Hilbert space. For unbounded A’s we consider weak solutions in a larger space H<sub>T</sub>, …
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Box approximation and related techniques in spectral theory
… system r [arrow] Ar, where Ar is the truncated Wiener-Hopf operator surrounded by operators of multiplication by the function e[superscript alpha/2] [absolute value of dot], [alpha][greater than] 0. We show that in the case when the symbol of the Wiener-Hopf operator is a rational function with …
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Mathematical modelling and optimal multivariable control of chemical processes
… hierarchical structure. A modern rnultivariable Wiener-Hopf controller has been applled to the plant model. The application has revealed a limitation condition that the plant matrix should be positive-definite along the infinite frequency axis. A new multi variable control theory has emerged fram …
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Mathematical Modelling of Acoustic Diffraction Noise Embracing Diverse Boundary Conditions
… within these models. Part I, "Applying the Wiener–Hopf Technique to Diverse Diffraction Problems in Acoustics", develops a generalised theory to solve diffraction problems with linear boundary conditions prescribed distinctly on each side of a semi-infinite boundary. We choose this framework …
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Oscillations and waves in anisotropic plasmas
… for the longitudinal plasma wave problem, the Wiener-Hopf factorization of the fixed frequency longitudinal plasma dispersion function is presented and the coupled nonlinear integral equations for the Wiener-Hopf factors are studied. These Wiener-Hopf factors are required in the construction of …
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Dynamic Analysis of Interfacial Cracks in Composite Laminates
… are considered. An integral transform, the Wiener-Hopf technique, and an asymptotic theory have been used for deriving the orders of stress singularity of interfacial cracks. The crack-tip elements in anisotropic materials are formulated by employing Lekhnitskii's stress functions and the …
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An investigation of the Oseen differential equations for the boundary layer
… first shores-up some of the theory on using the Wiener-Hopf technique to determine the solution of the integral equation of Oseen flow past a semi-infinite flat plate. The procedure is introduced and it divides into two steps; first is to transform the Oseen equation (Oseen 1927) into an integral …
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Multigroup transport equations with nondiagonal cross section matrices
… matrix, the problem is solved completely via the Wiener-Hopf method. For more general problems, generalized Chandrasekhar H equations are derived. A numerical method for their solution is proposed. Also, the exit distribution is written in terms of the H functions.
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Acoustic scattering in waveguides with smoothly-varying or discontinuous elastic boundaries
… of the two problems are solved using the Wiener-Hopf technique. This provides a check on the varying-parameter solutions as well as being of interest in itself.
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Scattering by porous aerofoil adaptations
… This can be achieved by solving certain matrix Wiener—Hopf problems. To do this, we present an effective numerical implementation of a previously proposed iterative method. We also derive a singular integral equation amenable to direct solution by a spectrally accurate method. This approach …
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The scattering of sound waves in two-dimensional ducts with discontinuities in height and material property
… (for the case of no height discontinuity) the Wiener-Hopf technique.
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Cascade analysis and synthesis of transfer functions of infinite dimensional linear systems
… systems is again admissible and that a Wiener-Hopf factorization problem can be solved just as in the finite-dimensional case. For the class of regular systems, it is shown that the cascade connection of a rational stable and antistable system has an additive stable-antistable …
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Studies on quadratic matrix equations and riccati differential equations associated with regular m-matrices
… matrix equations of this kind arise in noisy Wiener-Hopf problems for Markov chains. The solution of practical interest is a special M-matrix solution. The existence and uniqueness of M-matrix solutions and some numerical methods for nding the required M-matrix solution are studied by …
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A functional analytic approach to multigroup transport theory
… terms of two matrices X and Y which provide the Wiener-Hopf factorization of the dispersion matrix. The method applied yields compact results avoiding the calculation of adjoint solutions and normalization integrals to determine the expansion coefficients. Since the method proves to be amenable …
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Acoustic diffraction from a semi-infinite elastic plate under arbitrary fluid loading with application to scattering from Arctic ice leads
… solved using an analytic approach based on the Wiener-Hopf method. By low-frequency it is meant that the elastic properties of the plate are adequately described by the thin plate equation (kH ≲ 1). The diffraction problem relates to issues in long range sound propagation through partially …
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An investigation into the performance of a power-of-two coefficient transversal equalizer in a 34Mbit/s QPSK digital radio during frequency-selective fading conditions
… of this theory is presented in the form of Wiener Filter theory and the Wiener-Hopf equations. An adaptive equalizer located in a 34MBit/s QPSK digital radio is required to operate at very high speed, and its digital hardware implementation is not a trivial task. In order to reduce the cost …
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Analytical Methods For Levy Processes With Applications To Finance
… objects from the theory of Levy processes: the Wiener-Hopf factors and the exponential functional. We pay special attention to techniques and results associated with two “analytically tractable” families of processes known as the meromorphic and hyper-exponential families. We also demonstrate …
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Acoustic Scattering by Gratings
… techniques for infinite gratings, such as the Wiener--Hopf technique. It is found that the novel method shows much greater flexibility around the lengths of the apertures; furthermore, the evaluation of the scattered field is easier and faster. This work further extends to problems that have …
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