11,857 research outputs found
GLOBAL AGRICULTURAL REFORM AND U.S. AGRICULTURAL ADJUSTMENT CAPACITY
This paper focuses on U.S. agriculture response to policy reform. A growing body of empirical literature describes the potential aggregate gains for the U.S. markets if global agricultural tariffs and subsidies can be further reduced (USDA, 2001; World Bank, GEP 2002; Tokarick, 2003). These gains are based on an aggregation of expected responses at the micro-level, by firms and households, to changing market conditions. Some of them will be "gainers" whose current economic activities and assets will benefit from the new opportunities presented by policy reform. Some will be "losers" who are adversely affected by the reduction or loss of subsidies or import protection.Agricultural and Food Policy,
The Uncertainty of Fluxes
In the ordinary quantum Maxwell theory of a free electromagnetic field,
formulated on a curved 3-manifold, we observe that magnetic and electric fluxes
cannot be simultaneously measured. This uncertainty principle reflects torsion:
fluxes modulo torsion can be simultaneously measured. We also develop the
Hamilton theory of self-dual fields, noting that they are quantized by
Pontrjagin self-dual cohomology theories and that the quantum Hilbert space is
Z/2-graded, so typically contains both bosonic and fermionic states.
Significantly, these ideas apply to the Ramond-Ramond field in string theory,
showing that its K-theory class cannot be measured.Comment: 33 pages; minor modifications for publication in Commun. Math. Phy
Practical entomology : insects injurious to farm and garden crops, the character of the injury, the insect causing it, the remedy, briefly and plainly stated
The Phoenix Deep Survey: Extremely Red Galaxies and Cluster Candidates
We present the results of a study of a sample of 375 Extremely Red Galaxies
(ERGs) in the Phoenix Deep Survey, 273 of which constitute a subsample which is
80% complete to K_s = 18.5 over an area of 1160 arcmin^2. The angular
correlation function for ERGs is estimated, and the association of ERGs with
faint radio sources explored. We find tentative evidence that ERGs and faint
radio sources are associated at z > 0.5. A new overdensity-mapping algorithm
has been used to characterize the ERG distribution, and identify a number of
cluster candidates, including a likely cluster containing ERGs at 0.5 < z < 1.
Our algorithm is also used in an attempt to probe the environments in which
faint radio sources and ERGs are associated. We find limited evidence that the
I - K_s > 4 criterion is more efficient than R - K_s > 5 at selecting dusty
star-forming galaxies, rather than passively evolving ERGs.Comment: 14 emulateapj pages, 15 figures, 1 table, accepted for publication in
Astronomical Journal. A version with full resolution figures is available at
http://www.physics.usyd.edu.au/~asmith/research/ERGpaper.pd
Reusable Agena study. Volume 2: Technical
The application of the existing Agena vehicle as a reusable upper stage for the space shuttle is discussed. The primary objective of the study is to define those changes to the Agena required for it to function in the reusable mode in the 100 percent capture of the NASA-DOD mission model. This 100 percent capture is achieved without use of kick motors or stages by simply increasing the Agena propellant load by using optional strap-on-tanks. The required shuttle support equipment, launch and flight operations techniques, development program, and cost package are also defined
Turbine Disk Retirement-for-Cause: Measurement of Inspection Uncertainty for Disk Eddy Current Inspections
Major cost savings are possible through life extension of high-cost jet engine components until damage develops. Retirement-for-cause (RFC) decisions will be based upon both non-destructive inspection (NDI) to detect and size defects, and engineering analysis to assess defect severity under future usage. Failure Analysis Associates is performing a three-year program for ARPA/AFML to define and verify an optimum RFC strategy for jet engine disks. In depth, quantitative characterization of NDI performance is a major part of this project. This presentation summarizes the quantitative evaluation of inspection (NDI) uncertainty for four independent inspections - two state-of-the-art eddy current inspections of disk bolt holes, one with conventional hardware but improved signal processing, and one higher resolution eddy current inspection system assembled for this project. Separate inspections of the same 490 bolt holes in 49, 3rd stage disks retired from service in TF33 engines were performed with each of the four NDI techniques. Inspection results were compared with each other and with the actual cracks measured by surface plastic replicas and selected destructive metallography. The variation of detection probability and sizing errors with flaw size and indication level is defined in a form suitable.for the probabilistic reliability analysis and RFC strategy formulation. Progress in the other project tasks, especially the stress and fracture mechanics analysis to define the conditional failure probability if a flaw of specified size were present will also be summarized
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