ARE U.S. FARM PROGRAMS GOOD PUBLIC POLICY? TAKING POLICY PERFORMANCE SERIOUSLY

Distributional analysis is employed to assess the ethical acceptability of agricultural policy along plurastic moral criteria. Using 1999 micro-data from USDA ARMS survey and the Federal Reserve's Survey of Consumer Finances, we discuss policy performance (measured as the effect of direct government payments on the distribution of incomes and profits) relative to policy goals. We show that current programs only minimally address the post-?farm problem? objective of providing a safety net, and the goal of providing an abundant supply of agricultural products is potentially well-implemented given institutional constraints.Agricultural and Food Policy,

Structural tailoring of counter rotation propfans

The STAT program was designed for the optimization of single rotation, tractor propfan designs. New propfan designs, however, generally consist of two counter rotating propfan rotors. STAT is constructed to contain two levels of analysis. An interior loop, consisting of accurate, efficient approximate analyses, is used to perform the primary propfan optimization. Once an optimum design has been obtained, a series of refined analyses are conducted. These analyses, while too computer time expensive for the optimization loop, are of sufficient accuracy to validate the optimized design. Should the design prove to be unacceptable, provisions are made for recalibration of the approximate analyses, for subsequent reoptimization

Structural tailoring of advanced turboprops

The Structural Tailoring of Advanced Turboprops (STAT) computer program was developed to perform numerical optimization on highly swept propfan blades. The optimization procedure seeks to minimize an objective function defined as either: (1) direct operating cost of full scale blade or, (2) aeroelastic differences between a blade and its scaled model, by tuning internal and external geometry variables that must satisfy realistic blade design constraints. The STAT analysis system includes an aerodynamic efficiency evaluation, a finite element stress and vibration analysis, an acoustic analysis, a flutter analysis, and a once-per-revolution forced response life prediction capability. STAT includes all relevant propfan design constraints

Multiscale probability mapping: groups, clusters and an algorithmic search for filaments in SDSS

We have developed a multiscale structure identification algorithm for the detection of overdensities in galaxy data that identifies structures having radii within a user-defined range. Our "multiscale probability mapping" technique combines density estimation with a shape statistic to identify local peaks in the density field. This technique takes advantage of a user-defined range of scale sizes, which are used in constructing a coarse-grained map of the underlying fine-grained galaxy distribution, from which overdense structures are then identified. In this study we have compiled a catalogue of groups and clusters at 0.025 < z < 0.24 based on the Sloan Digital Sky Survey, Data Release 7, quantifying their significance and comparing with other catalogues. Most measured velocity dispersions for these structures lie between 50 and 400 km/s. A clear trend of increasing velocity dispersion with radius from 0.2 to 1 Mpc/h is detected, confirming the lack of a sharp division between groups and clusters. A method for quantifying elongation is also developed to measure the elongation of group and cluster environments. By using our group and cluster catalogue as a coarse-grained representation of the galaxy distribution for structure sizes of <~ 1 Mpc/h, we identify 53 filaments (from an algorithmically-derived set of 100 candidates) as elongated unions of groups and clusters at 0.025 < z < 0.13. These filaments have morphologies that are consistent with previous samples studied.Comment: 22 pages, 14 figures and 6 tables. Accepted for publication in MNRAS. Data products, three-dimensional visualisations and further information about MSPM can be found at http://www.physics.usyd.edu.au/sifa/Main/MSPM/ . v2 contains two additional references. v3 has a slightly altered title and updated reference

Improving the Measurement and Analysis of African Agricultural Productivity: Promoting Complementarities between Micro and Macro Data

Productivity Analysis,

Structure of the clean Ta(100) surface

The clean Ta(100) surface and some aspects of hydrogen adsorption have been studied by LEED and AES. The thorough examination of LEED patterns did not provide any evidence for an atomic reconstruction of the clean surface over the entire temperature range investigated, 150–600 K. The r-factor analysis used for comparison between measured and calculated I–V spectra yields a contraction of the topmost layer spacing of about 11% and an expansion of the second layer spacing of about 1% compared to the bulk value. The hydrogen adsorption does not induce any superstructures, but small hydrogen exposures lass then 1 L influence I–V spectra substantially