Northrop Corporation

About: Northrop Corporation is a based out in . It is known for research contribution in the topics: Laser & Signal. The organization has 1629 authors who have published 1509 publications receiving 20997 citations. The organization is also known as: Northrop Corporation.

A doublet-lattice method for calculating lift distributions on oscillating surfaces in subsonic flows.

Abstract: Approximate solutions from the linearized formulation are obtained by idealizing the surface as a set of lifting elements which are short line segments of acceleration-potential doub? lets. The normal velocity induced by an element of unit strength is given by an integral of the subsonic kernel function. The load on each element is determined, by, satisfying normal velocity boundary conditions at a set of points oil the surface. It is seen a posteriori

Angle-multiplexed storage of 5000 holograms in lithium niobate.

Abstract: As many as 5000 holograms of high-resolution images (320 × 220 pixels) have been stored within a single crystal of Fe:LiNbO3. The nominal angle between the reference beam and the object beam was 90°. Fractal-space multiplexing was used to increase the storage bandwidth.

Wavelet transforms and atmopsheric turbulence.

Abstract: Wavelet cross spectra and cross scalograms are used to analyze the time-scale structure of bivariate turbulence data from the boundary layer over the ocean. The cross scalogram for the streamwise and vertical turbulent velocity components shows a highly intermittent pattern with significant contributions of opposite signs appearing at two specific scales, ∼60 m and ∼2 km, believed to be related to small-scale turbulent mixing and large-scale secondary flow in the boundary layer

Shadow-corrected electromagnetic scattering from a randomly rough surface

Abstract: The problem of electromagnetic scattering from a randomly rough surface is analyzed in the high-frequency limit with the use of the Kirchhoff approximation in conjunction with the vector Kirchhoff equation. The surface is allowed to have a finite conductivity but is assumed to be homogeneous. The analysis does not require that the surface be described as a Gaussian process; however, explicit formulas are presented for this case. A major new consideration is the effect of shadowing by the surface on its ability to scatter energy.

Interaction between a circular inclusion and an arbitrarily oriented crack

Abstract: The plane interaction problem for a circular elastic inclusion embedded in an elastic matrix which contains an arbitrarily oriented crack is considered. Using the existing solutions for the edge dislocations as Green's functions, first the general problem of a through crack in the form of an arbitrary smooth arc located in the matrix in the vicinity of the inclusion is formulated. The integral equations for the line crack are then obtained as a system of singular integral equations with simple Cauchy kernels. The singular behavior of the stresses around the crack tips is examined and the expressions for the stress-intensity factors representing the strength of the stress singularities are obtained in terms of the asymptotic values of the density functions of the integral equations. The problem is solved for various typical crack orientations and the corresponding stress-intensity factors are given.