84,050 research outputs found
Instanton-like Excitations in 2D Fermionic Field Theory
New non-perturbatives excitations in the massless Thirring and Schwinger
models are discussed.Comment: Revtex, 9pp, to be published in New Trends in Theoretical Physic
FORTRAN optical lens design program
Computer program uses the principles of geometrical optics to design optical systems containing up to 100 planes, conic or polynomial aspheric surfaces, 7 object points, 6 colors, and 200 rays. This program can be used for the automatic design of optical systems or for the evaluation of existing optical systems
Reduced basis method for computational lithography
A bottleneck for computational lithography and optical metrology are long
computational times for near field simulations. For design, optimization, and
inverse scatterometry usually the same basic layout has to be simulated
multiple times for different values of geometrical parameters. The reduced
basis method allows to split up the solution process of a parameterized model
into an expensive offline and a cheap online part. After constructing the
reduced basis offline, the reduced model can be solved online very fast in the
order of seconds or below. Error estimators assure the reliability of the
reduced basis solution and are used for self adaptive construction of the
reduced system. We explain the idea of reduced basis and use the finite element
solver JCMsuite constructing the reduced basis system. We present a 3D
optimization application from optical proximity correction (OPC).Comment: BACUS Photomask Technology 200
End-wall boundary layer measurements in a two-stage fan
Detailed flow measurements made in the casing boundary layer of a two-stage transonic fan are summarized. These measurements were taken at a station upstream of the fan, between all blade rows, and downstream of the last row. Conventional boundary layer parameters were calculated from the measured data. A classical two dimensional casing boundary layer was measured at the fan inlet and extended inward to approximately 15 percent of span. A highly three dimensional boundary layer was measured at the exit of each blade row and extended inward to approximately 10 percent of span. The steep radial gradient of axial velocity noted at the exit of the rotors was reduced substantially as the flow passed through the stators. This reduced gradient is attributed to flow mixing. The amount of flow mixing was reflected in the radial redistribution of total temperature as the flow passed through the stators. The blockage factors calculated from the measured data show an increase in blockage across the rotors and a decrease across the stators. For this fan the calculated blockages for the second stage were essentially the same as those for the first stage
Rigorous Simulations of 3D Patterns on Extreme Ultraviolet Lithography Masks
Simulations of light scattering off an extreme ultraviolet lithography mask
with a 2D-periodic absorber pattern are presented. In a detailed convergence
study it is shown that accurate results can be attained for relatively large 3D
computational domains and in the presence of sidewall-angles and
corner-roundings.Comment: SPIE Europe Optical Metrology, Conference Proceeding
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