A method to include machine manufacturing energy in energy balance analysis

Manufacturing and also maintenance and repair energy demand is hard to find, there are only few research data available and this data seems no to be very reliable. Manufacturing energy damand can be calculated by estimating the mean tractor usage and calculating the manufacturing energy per consumed fuel liter. In this way it is easy to estimate the manufacturing energy, because it can be calculated with the liter/ha figures. Fuel consumption for different works in the form of liter/ha can easily be found in literature

Cold Collision Frequency Shift in Two-Dimensional Atomic Hydrogen

We report a measurement of the cold collision frequency shift in atomic hydrogen gas adsorbed on the surface of superfluid 4He at T<=90 mK. Using two-photon electron and nuclear magnetic resonance in 4.6 T field we separate the resonance line shifts due to the dipolar and exchange interactions, both proportional to surface density sigma. We find the clock shift Delta v_c = -1.0(1)x10^-7 Hz cm^-2 x sigma, which is about 100 times smaller than the value predicted by the mean field theory and known scattering lengths in the 3D case.Comment: 4 pages, 3 figure

Barley β-amylase and β-glucanase activities at germination in vulgare-type lines from backcrosses of wild, spontaneum strains with cv. Adorra

Two hundred and nineteen lines derived from the backcross progenies of eight different Hordeum spontaneum strains were evaluated for β-amylase and β-glucanase activity five days after germination under aseptic conditions. The activities were determined on the basis of soluble protein or grain mass. The recurrent parent cultivar, Adorra, served as the standard. Putative recombinants with high B-amylase activity were relatively easily achieved from high-activity strains of H. spontaneum. Recombinants with high β-glucanase were rare. They appear to be eliminated, possibly due to the strong selection for the domesticated phenotype during the derivation process

Environment simulator for studying automatic crop farming

Agricultural machines capable of utilizing variable rate application technology are tackling spatial variability in agricultural fields.  Agricultural field robots are the next step in technology, robots which are capable of utilizing sensor and actuating technologies without human contact and operate only areas of interest.  However, agricultural field robots are still under research.  Robots are just one part of the next generation of crop farming having more advanced tools to do the work which currently requires humans.  The next generation of crop farming, in the vision of the authors, is based on automation, which incorporates stationary and moving sensors systems, robots, model based decision making, automated operation planning which adapts to spatial variability according to the measurements as well as to weather conditions.  This article presents a top-down approach of automated crop farming using simulation, trying to cover all the component parts on a fully automated farm.  In the article, the developed simulation platform is presented as well as sample simulation results.  The environment simulator is based on crop growth models, weed growth models, soil models, spatial variation generation and weather statistics.  Models for the environment were found in literature and were tailored and tuned to fit the simulation purposes, to form a collection of models.  The collection of models was evaluated by using sensitivity analysis.  Furthermore, a full scale scenario was simulated over one season, incorporating 9000 spatial cells in five fields of a farm.   Keywords: robots, crop growth models, soil water models, decision making, operation plannin

Energy consumption in animal production : case farm study

v2012o

On the formation mechanism of impurity-helium solids: evidence for extensive clustering

Optical emission studies on a discharged nitrogen-helium gas jet injected into superfluid helium near 1.5 K are described. The analysis of atomic (a-group) and molecular Vegard-Kaplan transitions clearly indicates that the emitting species are embedded in the nitrogen clusters. The formation of the clusters is most efficient in the crater formed on the liquid surface. The model calculations based on the classical bubble model and density functional theory suggest that under the experimental conditions only clusters consisting of more than 1000 molecules have a kinetic energy sufficient for the stable cavity formation inside liquid helium. The results obtained suggest that the formation of impurity-helium solids is a consequence of extensive clustering in the gas jet