Results 241 to 250 of about 5,581,859 (291)

Source splitting via the point source method

Inverse Problems, 2010
We introduce a new algorithm for source identification and field splitting based on the point source method (Potthast 1998 A point-source method for inverse acoustic and electromagnetic obstacle scattering problems IMA J. Appl. Math. 61 119–40, Potthast R 1996 A fast new method to solve inverse scattering problems Inverse Problems 12 731–42).
Potthast, Roland, Fazi, Filippo, Nelson, Philip A.   +2 more
openaire   +2 more sources

Auxiliary source point method: the Laplace equation

Engineering Analysis with Boundary Elements, 1987
Abstract A new boundary collocation method is demonstrated using auxiliary source points located outside the normal boundary. It is shown that this eliminates the intermediate integration step normally found in boundary element methods and the approximating function can be found simply by a matrix inversion.
H.M. Cekirge, W.J. Lehr
openaire   +2 more sources

A point source/point receiver method for ultrasonic testing

1993 Proceedings IEEE Ultrasonics Symposium, 1993
Much of the theory and practice of ultrasonic testing involves the use of the plane wave approximation and of transducers large enough to generate planar wavefronts. Motivated in part by the emergence of engineering materials for which conventional techniques become impractical, the research reported here addresses the use of spherical waves generated ...
N.N. Hsu, C.H. Palmer, S.E. Fick
openaire   +1 more source

The Role of Point Sources and Their Power Fluxes in the Linear Sampling Method

SIAM Journal on Applied Mathematics, 2011
The authors investigate the role of point sources and their power fluxes in the linear sampling method (LSM). They analyze the mechanism of power flux transport throughout the background medium for acoustic waves from both a global and local view point: in the later case, the importance of the flow tubes of the scattered field is highlighted.
R. Aramini, CAVIGLIA, GIACOMO, G. Giorgi
openaire   +2 more sources

A Point Light Source Interference Removal Method for Image Dehazing

2020 IEEE/CVF Conference on Computer Vision and Pattern Recognition Workshops (CVPRW), 2020
Single image haze removal has been a challenging problem and the performance of the most existing dehazing methods is degraded when point light sources exist in the hazy image. In this paper, we propose a point light source interference removal method (PLiSIR) to reduce the interferences when estimating the atmospheric light.
Yanyang Yan, Shengdong Zhang, Mingye Ju, Wenqi Ren, Rui Wang 0032, Yuanfang Guo   +5 more
openaire   +1 more source

Complex point-source representation of real point sources and the Gaussian beam summation method

Journal of the Optical Society of America A, 1986
A new exact representation for point sources is given in terms of complex point sources. In the simplest configuration, a point source is equivalent to a distribution of sources on the surface of a sphere in complex space. The representation can be used to consider the propagation of point disturbances through inhomogeneous media and across interfaces.
openaire   +1 more source

TIR collimator designs based on point source and extended source methods

SPIE Proceedings, 2015
TIR collimator are essential illumination components demanding high efficiency, accuracy, and uniformity. Various illumination design methods have been developed for different design domains, including tailoring method, design via optimization, mapping and feedback method, and the simultaneous multiple surface (SMS) method.
T. Talpur, A. Herkommer
openaire   +1 more source

A method for predicting odour frequencies from a point source

Atmospheric Environment (1967), 1972
Abstract It is demonstrated that a fluctuating plume dispersion model can be used to give realistic estimates of odour frequencies around a point source, when the odour threshold of the chimney gases is determined by sensory methods ( Lindvall , 1970). The theoretical calculations are compared with observational results from a field experiment at and
openaire   +2 more sources

A subspace decomposition method for point source localization in blurred images

Proceedings of ICASSP '94. IEEE International Conference on Acoustics, Speech and Signal Processing, 2002
We address the problem of resolving blurred point sources in intensity images. A new approach to image restoration is introduced which is a 2-D generalization of techniques originating from the field of direction of arrival estimation (DOA). In the 2-D frequency domain, algorithms, such as MUSIC, may be adapted to search for these point sources.
Metin Gunsay, Brian D. Jeffs
openaire   +1 more source