38,863 research outputs found
Optimal Trajectories for Near-Earth-Objects Using Solar Electric Propulsion (SEP) and Gravity Assisted Maneuver
The future interplanetary missions will probably use the conventional chemical rockets to leave the sphere of influence of the Earth, and solar electric propulsion (SEP) to accomplish the other maneuvers of the mission. In this work the optimization of interplanetary missions using solar electric propulsion and Gravity Assisted Maneuver to reduce the costs of the mission, is considered. The high specific impulse of electric propulsion makes a Gravity Assisted Maneuver 1 year after departure convenient. Missions for several Near Earth Asteroids will be considered. The analysis suggests criteria for the definition of initial solutions demanded for the process of optimization of trajectories. Trajectories for the asteroid 2002TC70 are analyzed. Direct trajectories, trajectories with 1 gravity assisted from the Earth and with 2 gravity assisted from the Earth and either Mars are present. An indirect optimization method will be used in the simulations
Mott-insulator phase of coupled 1D atomic gases in a 2D optical lattice
We discuss the 2D Mott insulator (MI) state of a 2D array of coupled finite
size 1D Bose gases. It is shown that the momentum distribution in the lattice
plane is very sensitive to the interaction regime in the 1D tubes. In
particular, we find that the disappearance of the interference pattern in time
of flight experiments will not be a signature of the MI phase, but a clear
consequence of the strongly interacting Tonks-Girardeau regime along the tubes.Comment: 4 pages, 3 figure
Magnetic Properties of the Metamagnet Ising Model in a three-dimensional Lattice in a Random and Uniform Field
By employing the Monte Carlo technique we study the behavior of Metamagnet
Ising Model in a random field. The phase diagram is obtained by using the
algorithm of Glaubr in a cubic lattice of linear size with values ranging
from 16 to 42 and with periodic boundary conditions.Comment: 4 pages, 6 figure
Aplicação de ácido húmico via fertirrigação na produtividade da bananeira BRS Tropical.
Os ácidos húmicos constituem a maior fração da matéria orgânica do solo. A parte mais estável do carbono presente na matéria orgânica do solo e são cruciais no conceito de desenvolvimento sustentável, devido à sua influência na manutenção da qualidade do solo
Knizhnik-Zamolodchikov-Bernard equations connected with the eight-vertex model
Using quasiclassical limit of Baxter's 8 - vertex R - matrix, an elliptic
generalization of the Knizhnik-Zamolodchikov equation is constructed. Via
Off-Shell Bethe ansatz an integrable representation for this equation is
obtained. It is shown that there exists a gauge transformation connecting this
equation with Knizhnik-Zamolodchikov-Bernard equation for SU(2)-WZNW model on
torus.Comment: 20 pages latex, macro: tcilate
Análise da produção de fitohormônios por Gluconacetobacter diazotrophicus influenciada pelas condições de operação de um bioreator em batelada.
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