17,157 research outputs found
QUARTERLY ECONOMETRIC ANALYSIS OF U.S. SOYBEAN MARKET
This article is the further development and refinement of quarterly models of U.S. field crops, drawing upon the theory of pricing, production, and storage under uncertainty. The decisions of storage industry and farm production are taken into account. The findings of this research are both methodological and empirical.Crop Production/Industries, Research Methods/ Statistical Methods, Risk and Uncertainty,
ECONOMIC EFFECTS OF U.S. DAIRY PROGRAMS
Based on econometric analysis, this article estimates effects of terminating the milk order system and milk price support, singly and together, over the period 1966-90. Since 1980, milk orders have raised the national blend price by 1-2%; price support has raised the blend price to well above the market clearing price, by over 21% in 1983. Short- and long-run benefits and costs are estimated for various policy options under 1990 conditions.Agricultural and Food Policy,
Tailoring Accelerating Beams in Phase Space
An appropriate design of wavefront will enable light fields propagating along
arbitrary trajectories thus forming accelerating beams in free space. Previous
ways of designing such accelerating beams mainly rely on caustic methods, which
start from diffraction integrals and only deal with two-dimensional fields.
Here we introduce a new perspective to construct accelerating beams in phase
space by designing the corresponding Wigner distribution function (WDF). We
find such a WDF-based method is capable of providing both the initial field
distribution and the angular spectrum in need by projecting the WDF into the
real space and the Fourier space respectively. Moreover, this approach applies
to the construction of both two- and three-dimensional fields, greatly
generalizing previous caustic methods. It may therefore open up a new route to
construct highly-tailored accelerating beams and facilitate applications
ranging from particle manipulation and trapping to optical routing as well as
material processing.Comment: 8 pages, 6 figure
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