Now showing items 61-70 of 102
An image deblurring method using diffraction gratings
(Elsevier, 1981-01-15)
A method of image deblurring is described, in which the restoration filter is derived from Ronchi rulings. Although two-dimensional spatial filtering is used, the method employs a line source, resulting in significant noise ...
Cardiac cine magnetic resonance fingerprinting for combined ejection fraction, T1 and T2 quantification
(Wiley Periodicals, Inc.Springer‐Verlag, 2020-08)
Interferometric gratings with phase correction
(Elsevier, 1974-06)
A technique for producing diffractive optical elements uses holographic methods to incorporate into the recorded fringe pattern a correction factor for the phase defect of the substrate.
Bias circuit instabilities and their effect on the d.c. current-voltage characteristics of double-barrier resonant tunneling diodes
(Elsevier, 1991-02)
Bias circuit stability has important implications for the study and application of double-barrier resonant tunneling structures. Stability criteria for resonant tunneling diodes are investigated for the common bias circuit ...
Design, fabrication and operation of a hot electron resonant tunneling transistor
(Elsevier, 1989-12)
Transistors employing resonant tunneling injection of hot electrons into a thin quantum well base region have been fabricated. The base region in these transistors is formed by a narrow bandgap material like InGaAs so that ...
Thick grating analysis of interferometrically produced waveguides
(Elsevier, 1975-06)
The thin grating decomposition method of thick grating analysis is used to analyze guiding effects in thick phase gratings having sinusoidal refractive index modulation.
Diffusion effects in short-channel GaAs MESFETs
(Elsevier, 1989-03)
Diffusion effects in short-channel GaAs MESFETs are studied using a two-dimensional electron temperature simulation. A structure that consists of two n+-n contacts on a thin channel region was used as a test vehicle for ...
Numerical modeling of abrupt heterojunctions using a thermionic-field emission boundary condition
(Elsevier, 1993-03)
We present a numerical model in which the thermionic and tunneling mechanisms across an abrupt heterojunction interface are taken into account on the basis of the one dimensional drift-diffusion formulation. We use an ...
Retrospective correction of surface coil MR images using an automatic segmentation and modeling approach
(John Wiley & Sons, Ltd., 1997-05)
The use of surface coils in magnetic resonance imaging offers significant improvements in the signal-to-noise ratio over volume coils for many applications. However, the inhomogeneous reception profile of surface coils ...