Results 241 to 250 of about 809,821 (285)
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Canadian Journal of Mathematics, 1986
Recently, Ferus ([5], [6]) classified connected Riemannian manifolds with parallel second fundamental form in a real space form of constant curvature . In this paper we may restrict our attention to isotropic submanifolds with parallel second fundamental form in the Euclidean sphere Sm(k) of constant curvature k. Due to Ferus, we find that an isotropic
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Recently, Ferus ([5], [6]) classified connected Riemannian manifolds with parallel second fundamental form in a real space form of constant curvature . In this paper we may restrict our attention to isotropic submanifolds with parallel second fundamental form in the Euclidean sphere Sm(k) of constant curvature k. Due to Ferus, we find that an isotropic
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The Quarterly Journal of Mathematics, 1986
Let E be an oriented real vector bundle equipped with a metric \(\beta\) of signature (p,q). Two results are proved. A regular full isotrope of (E,\(\beta)\) induces a \(Spin^ c\) structure for (E,\(\beta)\). A Spin structure for (E,\(\beta)\) induces a Spin structure for \((D^{\perp}/D,\beta_ D)\); likewise for \(Spin^ c\) structures. Here D is a real
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Let E be an oriented real vector bundle equipped with a metric \(\beta\) of signature (p,q). Two results are proved. A regular full isotrope of (E,\(\beta)\) induces a \(Spin^ c\) structure for (E,\(\beta)\). A Spin structure for (E,\(\beta)\) induces a Spin structure for \((D^{\perp}/D,\beta_ D)\); likewise for \(Spin^ c\) structures. Here D is a real
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Isotropic and semi-isotropic observations in cosmology
Classical and Quantum Gravity, 1994We investigate the geometric consequences for dust universes of isotropies within the set of idealized galactic observations---area distance, number counts, proper motions and image distortion. Anisotropy in the Hubble parameter is shown to indicate non-zero proper motions.
Maartens, R., Matravers, D. R.
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On the Spectrum of Isotropic Temperature Fluctuations in an Isotropic Turbulence
Journal of Applied Physics, 1951The one- and three-dimensional spectral equations for a field of isotropic temperature fluctuations in an isotropic turbulence are derived from the correlation equation. Then, except for the degenerate case of simple conductive decay, stationary fluctuation fields are postulated. Largely by dimensional reasoning and some simple postulates, forms of the
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The Decay of Isotropic Temperature Fluctuations in an Isotropic Turbulence
Journal of the Aeronautical Sciences, 1951The approach of von Karman and Howarth (to isotropic turbulence) has been applied to the decay of isotropic temperature fluctuations in a decaying isotropic turbulence, under the restriction that the temperature differences are too small to have any effect on the velocity field.
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IEEE Transactions on Information Theory, 1977
Rate-distortion functions for 2-dimensional homogeneous isotropic images are compared with the performance of five source encoders designed for such images. Both unweighted and frequency weighted mean-square error distortion measures are considered. The coders considered are a) differential pulse code modulation (DPCM) using six previous samples or ...
John Ben O'Neal Jr., T. Raj Natarajan
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Rate-distortion functions for 2-dimensional homogeneous isotropic images are compared with the performance of five source encoders designed for such images. Both unweighted and frequency weighted mean-square error distortion measures are considered. The coders considered are a) differential pulse code modulation (DPCM) using six previous samples or ...
John Ben O'Neal Jr., T. Raj Natarajan
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Hydrodynamics of isotropic ferrogels
Physical Review E, 2003We derive the complete set of macroscopic dynamic equations for ferrogels under an external magnetic field, including the magnetization as an independent dynamic degree of freedom. The magnetoelasticity comes in the form of magnetostriction and through the magnetic part of the Maxwell stress.
Jarkova, E. +3 more
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Pattern Recognition, 1995
Abstract Isotropic growth from a single point on a two-dimensional square grid should generate an increasing sequence of discretized discs. We present a simple probabilistic model for growth on a grid, and discuss a class of parameterizations of the model (called kernels) which was conjectured [S. Thompson and A. Rosenfeld, Discrete stochastic growth
Scott F. Thompson, Azriel Rosenfeld
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Abstract Isotropic growth from a single point on a two-dimensional square grid should generate an increasing sequence of discretized discs. We present a simple probabilistic model for growth on a grid, and discuss a class of parameterizations of the model (called kernels) which was conjectured [S. Thompson and A. Rosenfeld, Discrete stochastic growth
Scott F. Thompson, Azriel Rosenfeld
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On the geometry of isotropic arrays
IEEE Transactions on Signal Processing, 2003We consider array geometries whose direction-of-arrival (DOA) estimation performance is isotropic. An isotropic array is one whose Cramer-Rao bound (CRB) on the DOA of a single source is uniform for all angles. For both planar arrays and volume arrays we derive necessary and sufficient conditions on array element locations so that the array is ...
Ülkü Baysal, Randolph L. Moses
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On Generation of an Isotropic Field
SIAM Journal on Applied Mathematics, 1978An algorithm is presented to generate an isotropic field of two dimensions when one dimensional stationary data are given.
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