A group of small spacecraft able to change their relative position and attitude through the use of the potential function method is discussed. The spacecraft shapes, sizes and manoeuvring capabilities are not identical, although all are assumed to manoeuvre using continuous thrusters. A hyperbolic form of the attractive potential function is used to reduce actuator effort by using natural orbit...

In this paper, the Elzaki transform method is used for solving two-dimensional (2D) elasticity problems in plane polar coordinates. Airy stress function was used to express the stress compatibility equation as a biharmonic equation. Elzaki transform was applied with respect to the radial coordinate to a modified form of the stress compatibility equation, and the biharmonic equation simplified t...

to study of some cryoprotectives in cold tolerant rice genotypes (irctn33 and irctn34) and cold-sensitive rice genotype (hoveize) were selected in previous experiment, fourteen-day rice seedlings exposed fourteen days in 13/15oc (respectively night-day) temperatures as the stress treatment and 22/28oc (night-day) temperature as control treatment in phytotrone. this experiment was conducted in f...

abstract drought is the most important factor limiting crop yield word wide. osmotic adjustment (oa) and strong and deep root system result in increased cereal drought tolerance through increasing water uptake and water use efficiency. the impact of root structure and physiological traits on drought stress response was studied in three barley cultivars including yousof (drought tolerant), moroc...