14,027 research outputs found
A New Record of Scaphytopius Magdalensis: Another Plant Disease Vector in Michigan (Homoptera: Cicadellidae)
Excerpt: Several specimens of Scaphytopius magdalensis (Provancher) were collected by Burger (1966), and brought to the attention of the senior author for verification. This leafhopper, a vector of Blueberry Stunt, is widely distributed in the eastern United States, and southern Ontario and Quebec. This, the first record of a leafhopper virus vector for blueberries in Michigan, increases the list of leafhopper vectors of plant diseases in the state , given in Taboada and Hoffman (1965). to 14
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
Numerical analysis of nanostructures for enhanced light extraction from OLEDs
Nanostructures, like periodic arrays of scatters or low-index gratings, are
used to improve the light outcoupling from organic light-emitting diodes
(OLED). In order to optimize geometrical and material properties of such
structures, simulations of the outcoupling process are very helpful. The finite
element method is best suited for an accurate discretization of the geometry
and the singular-like field profile within the structured layer and the
emitting layer. However, a finite element simulation of the overall OLED stack
is often beyond available computer resources. The main focus of this paper is
the simulation of a single dipole source embedded into a twofold infinitely
periodic OLED structure. To overcome the numerical burden we apply the Floquet
transform, so that the computational domain reduces to the unit cell. The
relevant outcoupling data are then gained by inverse Flouqet transforming. This
step requires a careful numerical treatment as reported in this paper
Seasonality, precautionary savings and health uncertainty: Evidence from farm households in central Kenya
The high prevalence of risks in low income economies makes managing uncertainty critical for productivity and survival. This paper analyzes seasonal changes in farm households’ per capita consumption and saving in response to weather and health shocks. Using a sample of 196 households in central Kenya, it tests the notion that people save most of their transitory income, and examines their precautionary saving motives. The results show that the propensity to save out of transitory income is about a fifth of what the permanent income hypothesis postulates. The propensity to save differs by wealth, with the poor exhibiting stronger precautionary motives towards rainfall variability. But the wealth effect is weak, suggesting that the asset base is vulnerable even for the better-off. However, precautionary savings tend to increase with wealth among HIV/AIDS affected households. Since illness is associated with higher consumption, and therefore less investment, we find more volatile consumption for HIV/AIDS affected households
A Rigorous Finite-Element Domain Decomposition Method for Electromagnetic Near Field Simulations
Rigorous computer simulations of propagating electromagnetic fields have
become an important tool for optical metrology and design of nanostructured
optical components. A vectorial finite element method (FEM) is a good choice
for an accurate modeling of complicated geometrical features. However, from a
numerical point of view solving the arising system of linear equations is very
demanding even for medium sized 3D domains. In numerics, a domain decomposition
method is a commonly used strategy to overcome this problem. Within this
approach the overall computational domain is split up into smaller domains and
interface conditions are used to assure continuity of the electromagnetic
field. Unfortunately, standard implementations of the domain decomposition
method as developed for electrostatic problems are not appropriate for wave
propagation problems. In an earlier paper we therefore proposed a domain
decomposition method adapted to electromagnetic field wave propagation
problems. In this paper we apply this method to 3D mask simulation.Comment: 9 pages, 7 figures, SPIE conference Advanced Lithography / Optical
Microlithography XXI (2008
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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