U.S. Agriculture: Commercial and Large Producer Concentration and Implications for Agribusiness Segments

This study examines rate of concentration of farms and sales for aggregate farm production and crop and livestock activities during the 1982 to 2002 period. Data from the Census of Agriculture are used to calculate Theil's relative entropy measure as an indicator of concentration. Results indicate that Grain segments are lagging behind cotton, potato and hog segments in terms of concentration of total sales, while concentration in the dairy segment appears to be gaining steam. Agribusiness serving less concentrated industry segments should look to the more concentrated segments as leading indicators for effective marketing strategies as concentration increases.Concentration, Commodities, Entropy, Agribusiness,

U.S. Agriculture: Commercial and Large Producer Concentration and Implications for Agribusiness Segments

This study examines rate of concentration of farms and sales for aggregate farm production and crop and livestock activities during the 1982 to 2002 period. Data from the Census of Agriculture are used to calculate Theil's relative entropy measure as an indicator of concentration. Results indicate that Grain segments are lagging behind cotton, potato and hog segments in terms of concentration of total sales, while concentration in the dairy segment appears to be gaining steam. Agribusiness serving less concentrated industry segments should look to the more concentrated segments as leading indicators for effective marketing strategies as concentration increases.Concentration, Commodities, Entropy, Agribusiness,

Evaluation of the HARDMAN comparability methodology for manpower, personnel and training

The methodology evaluation and recommendation are part of an effort to improve Hardware versus Manpower (HARDMAN) methodology for projecting manpower, personnel, and training (MPT) to support new acquisition. Several different validity tests are employed to evaluate the methodology. The methodology conforms fairly well with both the MPT user needs and other accepted manpower modeling techniques. Audits of three completed HARDMAN applications reveal only a small number of potential problem areas compared to the total number of issues investigated. The reliability study results conform well with the problem areas uncovered through the audits. The results of the accuracy studies suggest that the manpower life-cycle cost component is only marginally sensitive to changes in other related cost variables. Even with some minor problems, the methodology seem sound and has good near term utility to the Army. Recommendations are provided to firm up the problem areas revealed through the evaluation

A comparison of minimum distance and maximum likelihood techniques for proportion estimation

The estimation of mixing proportions P sub 1, P sub 2,...P sub m in the mixture density f(x) = the sum of the series P sub i F sub i(X) with i = 1 to M is often encountered in agricultural remote sensing problems in which case the p sub i's usually represent crop proportions. In these remote sensing applications, component densities f sub i(x) have typically been assumed to be normally distributed, and parameter estimation has been accomplished using maximum likelihood (ML) techniques. Minimum distance (MD) estimation is examined as an alternative to ML where, in this investigation, both procedures are based upon normal components. Results indicate that ML techniques are superior to MD when component distributions actually are normal, while MD estimation provides better estimates than ML under symmetric departures from normality. When component distributions are not symmetric, however, it is seen that neither of these normal based techniques provides satisfactory results

Aerosol physical properties in the stratosphere (APPS) radiometer design

The measurement concepts and radiometer design developed to obtain earth-limb spectral radiance measurements for the Aerosol Physical Properties in the Stratosphere (APPS) measurement program are presented. The measurements made by a radiometer of this design can be inverted to yield vertical profiles of Rayleigh scatterers, ozone, nitrogen dioxide, aerosol extinction, and aerosol physical properties, including a Junge size-distribution parameter, and a real and imaginary index of refraction. The radiometer design provides the capacity for remote sensing of stratospheric constituents from space on platforms such as the space shuttle and satellites, and therefore provides for global measurements on a daily basis

Modeling Electromagnetic Disturbances in Closed-Loop Computer Controlled Flight Systems

High intensity electromagnetic radiation has been demonstrated to be a source of computer upsets in commercially available digital flight control systems. In this paper we introduce an electromagnetic disturbance model which can be used for stability analysis and augmentation of any such digitally implemented control law. The model is composed of a Markovian exosystem supplying radiation events to a discrete-time jump linear system which models how the radiation interferes with the nominal operation of the closed-loop system. We discuss how this model can be used to characterize stability and how it can be parametrized and validated in an experimental setting

PQChPT with Staggered Sea and Valence Ginsparg-Wilson Quarks: Vector Meson Masses

We consider partially quenched, mixed chiral perturbation theory with staggered sea and Ginsparg-Wilson valence quarks in order to extract a chiral-continuum extrapolation expression for the vector meson mass up to order O(a^2), at one-loop level. Based on general principles, we accomplish the task without explicitly constructing a sophisticated, heavy vector meson chiral Lagrangian.Comment: 12 pages, 1 figure, REVTe