Results 221 to 230 of about 703,061 (267)

Fourth order rotatability

Communications in Statistics - Simulation and Computation, 1985
Fourth order rotatable designs are discussed. A general k, design moment inequality is given. The variance function for two-factor designs is derived, and plotted for a specific design. A minimum point set requirement for two-factor designs is established, thus enabling one to form an infinity of such designs. Some difficulties in obtaining deLigns for
Norman R. Draper, Agnes M. Herzberg
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Nöther’s symmetries in fourth-order cosmologies

Il Nuovo Cimento B, 1994
Summary. -- We apply the so-called NSther Symmetry Approach to a generic fourth-order theory of gravity f(R) to integrate the dynamics connected with the pointlike FRW cosmological Lagrangian. We get interesting results when f(R) ~ R 3/2, since in this case the equations of motion are exactly solvable and solutions are physically relevant.
Capozziello, S., De Ritis, R.
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A fourth‐order extrapolation method for special nonlinear fourth‐order boundary value problems

Communications in Applied Numerical Methods, 1986
AbstractA fourth‐order convergent finite difference method is developed for the numerical solution of the nonlinear fourth‐order boundary value problem y(iv)(x) = f(x,y), a < x < b, y(a) = Ao,y″(a) = Bo, y(b) = A1, y″(b) = B1. The method is based on a second‐order converget method which is used on two grids, fourth‐order convergence being ...
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Quantum theory of fourth-order interference

Physical Review A, 1988
The quantum theory of fourth-order interference of light is presented in a general format and compared with classical wave theory. The conditions under which nonclassical phenomena occur are discussed. In particular, the interference between the quantum field and classical field may give rise to a nonclassical effect.
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On mixed methods for fourth-order problems

Computer Methods in Applied Mechanics and Engineering, 1980
A mixed finite element method for the problem v + σ2Δ2v = x with different types of boundary conditions is described. The method converges, and it is well suited for the analysis of various evolution problems. The computation of the discrete solution is made by applying a sequence of iterative methods for block matrices: correspondingly to each ...
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Fourth-Order Tensors

2009
Fourth-order tensors play an important role in continuum mechanics where they appear as elasticity and compliance tensors. In this section we define fourth-order tensors and learn some basic operations with them. To this end, we consider a set \(\mathcal{L}{\text{ in}}^{n}\) of all linear mappings of one second-order tensor into another one within ...
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FOURTH ORDER

AIAA Computational Fluid Dynamics Conference, 1973
E KRAUSE, E HIRSCHEL, W KORDULLA
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Fourth-Order Vacuum Polarization

Physical Review, 1952
Baranger, M., Dyson, F. J., Salpeter, E. E.   +2 more
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Fourth-order analogies to the Painlevé equations

Journal of Physics A: Mathematical and General, 2002
Summary: Using the compatibility condition for the Painlevé equations, several new fourth-order ordinary differential equations (ODEs) that are analogies of the Painlevé equations are found. Isomonodromic linear problems for these equations are given. Special solutions of the fourth-order ODEs obtained are discussed.
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Fourth-order spectra of mixture processes

International Conference on Acoustics, Speech, and Signal Processing, 2003
The hypothesis for non-Gaussian processes higher-order spectra contain information that usually is not contained in second-order spectra is proved for a special case of the trispectrum using mixture processes. Specifically, the fourth-order cumulant spectrum is shown to differentiate between a Gaussian process and a non-Gaussian mixture process ...
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