6,100 research outputs found
Effects of Agricultural Mechanization on Farm Income Patterns
This article is part of the seminar-workshop on the “Consequences of Small Farm Mechanization on Production, Employment and Incomes in the Philippines” sponsored jointly by the Ministry of Agriculture, the National Economic and Development Authority, the Philippine Institute for Development Studies and the International Rice Research Institute held on December 1-2, 1983 at Tagaytay City. Utilizing cross-section results from a survey conducted, this article measures the importance of mechanization as a source of income variation. Analysis supports the fact that mechanization has effects on income changes. However, this article encourages the use of multivariate analysis for a better assessment of its impact and the inclusion of factor share analysis to account for the distribution of ownership.income changes, agriculture sector, impact analysis, mechanization
Effects of Agricultural Mechanization on Farm Income Patterns
This article is part of the seminar-workshop on the “Consequences of Small Farm Mechanization on Production, Employment and Incomes in the Philippines” sponsored jointly by the Ministry of Agriculture, the National Economic and Development Authority, the Philippine Institute for Development Studies and the International Rice Research Institute held on December 1-2, 1983 at Tagaytay City. Utilizing cross-section results from a survey conducted, this article measures the importance of mechanization as a source of income variation. Analysis supports the fact that mechanization has effects on income changes. However, this article encourages the use of multivariate analysis for a better assessment of its impact and the inclusion of factor share analysis to account for the distribution of ownership.income changes, agriculture sector, impact analysis, mechanization
Beyond Organic: An Overview of Biodynamic Agriculture with Case Examples
A great deal of research has been done regarding economic and consumer aspects of organic agriculture. A different form of agriculture, called biodynamic agriculture, is emerging, with acreage located across the globe. Like organic agriculture, biodynamic agriculture has a certification process, but it has not received as much research attention from agricultural economists. This paper provides basic background information about biodynamic agriculture. In particular, it gives a count of certified biodynamic farms, by state, in the U.S., and it gives the most common products produced by those farms. Wine grapes are by far the most common biodynamic agricultural product. It also includes three case examples of firms employing this production system and business strategy. The diverse case examples were developed through telephone interviews with certified biodynamic agricultural producers. It is predicted that despite its growth, biodynamic agriculture will become neither a fad nor a trend. Rather, it will remain a background influence on organic and conventional agriculture.Research and Development/Tech Change/Emerging Technologies,
Super-AGB Stars and their role as Electron Capture Supernova progenitors
We review the lives, deaths and nucleosynthetic signatures of intermediate
mass stars in the range approximately 6.5-12 Msun, which form super-AGB stars
near the end of their lives. We examine the critical mass boundaries both
between different types of massive white dwarfs (CO, CO-Ne, ONe) and between
white dwarfs and supernovae and discuss the relative fraction of super-AGB
stars that end life as either an ONe white dwarf or as a neutron star (or an
ONeFe white dwarf), after undergoing an electron capture supernova. We also
discuss the contribution of the other potential single-star channels to
electron-capture supernovae, that of the failed massive stars. We describe the
factors that influence these different final fates and mass limits, such as
composition, the efficiency of convection, rotation, nuclear reaction rates,
mass loss rates, and third dredge-up efficiency. We stress the importance of
the binary evolution channels for producing electron-capture supernovae. We
discuss recent nucleosynthesis calculations and elemental yield results and
present a new set of s-process heavy element yield predictions. We assess the
contribution from super-AGB star nucleosynthesis in a Galactic perspective, and
consider the (super-)AGB scenario in the context of the multiple stellar
populations seen in globular clusters. A brief summary of recent works on dust
production is included. Lastly we conclude with a discussion of the
observational constraints and potential future advances for study into these
stars on the low mass/high mass star boundary.Comment: 28 pages, 11 figures. Invited review for Publications of the
Astronomical Society of Australia, to be published in special issue on
"Electron Capture Supernovae". Submitte
Curtailing the Dark Side in Non-Standard Neutrino Interactions
In presence of non-standard neutrino interactions the neutrino flavor
evolution equation is affected by a degeneracy which leads to the so-called
LMA-Dark solution. It requires a solar mixing angle in the second octant and
implies an ambiguity in the neutrino mass ordering. Non-oscillation experiments
are required to break this degeneracy. We perform a combined analysis of data
from oscillation experiments with the neutrino scattering experiments CHARM and
NuTeV. We find that the degeneracy can be lifted if the non-standard neutrino
interactions take place with down quarks, but it remains for up quarks.
However, CHARM and NuTeV constraints apply only if the new interactions take
place through mediators not much lighter than the electroweak scale. For light
mediators we consider the possibility to resolve the degeneracy by using data
from future coherent neutrino-nucleus scattering experiments. We find that, for
an experiment using a stopped-pion neutrino source, the LMA-Dark degeneracy
will either be resolved, or the presence of new interactions in the neutrino
sector will be established with high significance.Comment: 33 pages, 9 figures. Minor modifications. Version accepted for
publication in JHE
Interfacial chemistry of a perfluoropolyether lubricant studied by XPS and TDS
The interfacial chemistry of Fomblin Z25, a commercial perfluoropolyether used as lubricant for space applications, with different metallic surfaces: 440C steel, gold and aluminum was studied. Thin layers of Fomblin Z25 were evaporated onto the oxide-free substrates and the interfacial chemistry studied using XPS and TDS. The reactions were induced by heating the substrate and by rubbing the substrate with a steel ball. Gold was found to be completely unreactive towards Fomblin at any temperature. Reaction at room temperature was observed only in the case of the aluminum substrate, the most reactive towards Fomblin Z25 of the substrates studied. It was necessary to heat the 440C steel substrate to 190 degree C to induce decomposition of the fluid. The degradation of the fluid was indicated by the formation of a debris layer at the interface. This debris layer, composed of inorganic and organic reaction products, when completely formed, passivated the surface from further attack to the Fromblin on top. The tribologically induced reactions on 440C steel formed a debris layer of similar chemical characteristics to the thermally induced layer. In all cases, the degradation reaction resulted in preferential consumption of the difluoroformyl carbon (-OCF2O-)
Stock mechanics: a general theory and method of energy conservation with applications on DJIA
A new method, based on the original theory of conservation of sum of kinetic
and potential energy defined for prices is proposed and applied on Dow Jones
Industrials Average (DJIA). The general trends averaged over months or years
gave a roughly conserved total energy, with three different potential energies,
i.e. positive definite quadratic, negative definite quadratic and linear
potential energy for exponential rises (and falls), sinusoidal oscillations and
parabolic trajectories, respectively. Corresponding expressions for force
(impact) are also given. Keywords:Comment: 14 pages, 3 figures, scehudled for IJMPC 17/ issue
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