19,201 research outputs found
Algorithms for the determination of the time delays of the signal when using unequal detectors
In treating the recorded results from detectors at different locations in space, the analysis of the time delays of signals is crucial to locating the sources of detected radiation. Because the correlation method requires the manipulation of awkward matrices to evaluate its accuracy, a solution is outlined based on minimizing the sum of the squares of signal deviations, and the algorithms for evaluating the resulting error are presented
Mega Trends Driving Change within CES and Implications for Extension Economists
Many current trends affecting extension economist's education programs are found to be issues that go back 1/2 a century or more. Others involve issues that have been generally considered as part of economic theory, such as technology change. The emerging recasting of the social environment presents perhaps the most serious challenge to Extension economists program development.Teaching/Communication/Extension/Profession,
Identity and identification of Trogulus banaticus (Opiliones: Trogulidae) : a neglected species in the Northern Balkans
Trogulus banaticus Avram, 1971 is characterised and recorded as new for Slovenia. This species was previously mistaken for T. coriziformis C. L. Koch, 1839 and T. graecus Dahl, 1903 which were later rejected from the Slovenian fauna. T. banaticus is compared with the similar, and partly sympatric, T. tingiformis C. L. Koch, 1847 with which it has often been confused. A table of distinguishing characters for both species is provided, and the ecology of T. banaticus and its general distribution are discussed
APPLICATION OF RECURSIVE PARTITIONING TO AGRICULTURAL CREDIT SCORING
Recursive Partitioning Algorithm (RPA) is introduced as a technique for credit scoring analysis, which allows direct incorporation of misclassification costs. This study corroborates nonagricultural credit studies, which indicate that RPA outperforms logistic regression based on within-sample observations. However, validation based on more appropriate out-of-sample observations indicates that logistic regression is superior under some conditions. Incorporation of misclassification costs can influence the creditworthiness decision.finance, credit scoring, misclassification, recursive partitioning algorithm, Agricultural Finance,
Climate Effects on Rainfall Index Insurance Purchase Decisions
Rainfall Index insurance is a pilot insurance product offered to producers of hay and pasture in 9 states. This analysis examines the expected payoff of the RI insurance for bi-monthly periods based on rainfall shortage probabilities in alternative climate phases. Differences in expected returns indicate that selection of ENSO-specific optimal intervals may result in higher returns than those based on pooled rainfall series.rainfall insurance, ENSO, expected indemnity, Production Economics, Risk and Uncertainty,
Discussion: What Have We Learned from the New Suite of Risk Management Programs of the Food, Conservation, and Energy Act of 2008?
New revenue-based support programs in the 2008 Farm Bill represent a fundamental shift in farm programs and risk management decision-making. However, complexity, uncertainty, economics, and, arguably, an incomplete analysis of the new Average Crop Revenue Election (ACRE) program all contributed to low enrollment in the new program in 2009. An effective analysis of ACRE should consider farm programs as part of an integrated risk management portfolio, including crop insurance, marketing, and other risk management tools as opposed to a separate lottery program. Improving this integration could be one of the most significant consequences of the 2008 Farm Bill.farm bill, commodity programs, risk management, Agribusiness, Agricultural and Food Policy, Agricultural Finance, Farm Management, Land Economics/Use, Political Economy, Public Economics, Risk and Uncertainty, Q18,
Determinants of Agricultural Disaster Payments in the Southeastern U.S.: County Level Analysis
Using county level data we study if weather and climate variables or variables used as proxies for rent-seeking behavior determine disaster payment in the Southeast. We do not find evidence of rent-seeking but find that, in addition to weather, long term climate variables affect disaster payments.Farm Management, Risk and Uncertainty,
Radiative Transfer and Radiative driving of Outflows in AGN and Starbursts
To facilitate the study of black hole fueling, star formation, and feedback
in galaxies, we outline a method for treating the radial forces on interstellar
gas due to absorption of photons by dust grains. The method gives the correct
behavior in all of the relevant limits (dominated by the central point source;
dominated by the distributed isotropic source; optically thin; optically thick
to UV/optical; optically thick to IR) and reasonably interpolates between the
limits when necessary. The method is explicitly energy conserving so that
UV/optical photons that are absorbed are not lost, but are rather redistributed
to the IR where they may scatter out of the galaxy. We implement the radiative
transfer algorithm in a two-dimensional hydrodynamical code designed to study
feedback processes in the context of early-type galaxies. We find that the
dynamics and final state of simulations are measurably but only moderately
affected by radiative forces on dust, even when assumptions about the
dust-to-gas ratio are varied from zero to a value appropriate for the Milky
Way. In simulations with high gas densities designed to mimic ULIRGs with a
star formation rate of several hundred solar masses per year, dust makes a more
substantial contribution to the dynamics and outcome of the simulation. We find
that, despite the large opacity of dust to UV radiation, the momentum input to
the flow from radiation very rarely exceeds L/c due to two factors: the low
opacity of dust to the re-radiated IR and the tendency for dust to be destroyed
by sputtering in hot gas environments. We also develop a simplification of our
radiative transfer algorithm that respects the essential physics but is much
easier to implement and requires a fraction of the computational cost.Comment: 25 pages, 17 figures, submitted to MNRA
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