The problem of reorienting a spacecraft in to acquire a moving target is investigated. The spacecraft is modeled as a rigid body with N axisymmetric wheels controlled by axial torques, and the kinematics are represented by Modified Rodriques Parameters. The trajectory, denoted the reference trajectory, is one generated by a virtual spacecraft that is identical to the actual spacecraft. The open...

background and aims. infection control is an important issue in dentistry, and the dentists are primarily responsible for observing the relevant procedures. therefore, the present study evaluated knowledge, attitude, practice, and status of infection control among iranian dentists through systematic review of published results. materials and methods. in this systematic review, the required data...

The capability of attitude maneuvers and attitude tracking for spacecrafts is required in the current sophisticated space missions. In short, it is to obtain command requirements and attitude orientation after some form of control. With the development of space missions, the ability of rapid and energy-saved large-angle attitude maneuvers is actively expected. And the high requirements for the ...

background: fighting against cancers includes management in prevention, early treatment, and rehabilitation. this research is a descriptive study that was done to determine the women's knowledge attitude and practice about prevention of breast cancer. methods: the sample of this research included 630 women in kerman city, more than 15 years old, that selected in several stages (cluster, randomi...

The enhanced attitude control system experiment is a technology demonstration experiment on the NASA’s small spacecraft technology initiative program’s Lewis spacecraft to evaluate advanced attitude control strategies. The purpose of the enhanced attitude control system experiment is to evaluate the feasibility of designing and implementing robust multi-input/multi-output attitude control strat...