3,427 research outputs found
A conceptual design and operational characteristics for a Mars rover for a 1979 or 1981 Viking science mission
The feasibility of a small Mars rover for use on a 1979 or 1981 Viking mission was studied and a preliminary design concept was developed. Three variations of the concept were developed to provide comparisons in mobility and science capability of the rover. Final masses of the three rover designs were approximately 35 kg, 40 kg, and 69 kg. The smallest rover is umbilically connected to the lander for power and communications purposes whereas the larger two rovers have secondary battery power and a 2-way very high frequency communication link to the lander. The capability for carrying Viking rovers (including development system) to the surface of Mars was considered first. It was found to be feasible to carry rovers of over 100 kg. Virtually all rover systems were then studied briefly to determine a feasible system concept and a practical interface with the comparable system of a 1979 or 1981 lander vehicle
The Impact of Biofuel Production on Food Security: A Briefing Paper with a Particular Emphasis on Maize-to-Ethanol Production
A multi-feedstock approach is crucial for sustainable biofuel production in South Africa. In respect of ethanol production, biofuel producers should be allowed to draw on a range of starch-based crops including maize. A multi-feedstock approach will enable producers to select crops best suited to the agro-climate of the regions where their plants are situated and to minimize logistic costs by sourcing crops grown closest to their plants. In recent months, plans to use maize to produce ethanol have raised concerns that this could jeopardize food security in South Africa.biofuel production, food security, maize, Food Security and Poverty, Resource /Energy Economics and Policy, Q10, Q27,
Survey of attitudes of children in a remedial reading program as compared to children in a classroom reading program
The writer reviewed the literature involving the attitudes of children toward reading. It is with interest that the writer began her study in reviewing pertinent literature in identifying children who indicate poor attitudes toward reading and the reasons for this
Bio-ethanol Production from Wheat in the Winter Rainfall Region of South Africa: A Quantitative Risk Analysis
Contrary to developments in other parts of the world, South Africa has not developed a bio-ethanol industry. The objective was to quantify the risks and economic viability of a wheat based bio-ethanol plant in the winter rainfall region of South Africa. Monte Carlo simulation of a bio-ethanol plant was used to quantify the risk that investors will likely face. Under the Base scenario a 103 million liter bio-ethanol plant would not offer a reasonable chance of being economically viable. Alternative price enhancing policies were analyzed to determine policy changes needed to make a bio-ethanol plant economically viable in the region.biofuels, ethanol, risk analysis, simulation, economic viability, Simetar, SERF, Crop Production/Industries, Resource /Energy Economics and Policy,
Ultracold atoms in optical lattices with random on-site interactions
We consider the physics of lattice bosons affected by disordered on-site
interparticle interactions. Characteristic qualitative changes in the zero
temperature phase diagram are observed when compared to the case of randomness
in the chemical potential. The Mott-insulating regions shrink and eventually
vanish for any finite disorder strength beyond a sufficiently large filling
factor. Furthermore, at low values of the chemical potential both the
superfluid and Mott insulator are stable towards formation of a Bose glass
leading to a possibly non-trivial tricritical point. We discuss feasible
experimental realizations of our scenario in the context of ultracold atoms on
optical lattices.Comment: 4 pages, 3 eps figure
The generic mapping tools version 6
The Generic Mapping Tools (GMT) software is ubiquitous in the Earth and ocean sciences. As a cross-platform tool producing high-quality maps and figures, it is used by tens of thousands of scientists around the world. The basic syntax of GMT scripts has evolved very slowly since the 1990s, despite the fact that GMT is generally perceived to have a steep learning curve with many pitfalls for beginners and experienced users alike. Reducing these pitfalls means changing the interface, which would break compatibility with thousands of existing scripts. With the latest GMT version 6, we solve this conundrum by introducing a new "modern mode" to complement the interface used in previous versions, which GMT 6 now calls "classic mode." GMT 6 defaults to classic mode and thus is a recommended upgrade for all GMT 5 users. Nonetheless, new users should take advantage of modern mode to make shorter scripts, quickly access commonly used global data sets, and take full advantage of the new tools to draw subplots, place insets, and create animations.Funding Agency
National Science Foundation (NSF)
Appeared in article as
U.S. National Science Foundation
MSU Geological Sciences Endowmentinfo:eu-repo/semantics/publishedVersio
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