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In this paper, a continuous globally stable tracking control algorithm is proposed for spacecraft in the presence of unknown actuator failure. The design method is based on nonlinear dynamic inversion and  in contrast to traditional fault-tolerant control methods, the proposed controller does not require knowledge of the actuator faults and is implemented without explicit fault detection and isolation processes. The stability proof is based on a Lyapunov analysis and the properties of the singularity free quaternion representation of spacecraft dynamics. Results of numerical simulations state that the proposed controller is successful in achieving high attitude performance in the presence of external disturbances and actuator failures.

Background and Objectives: Patient education has an important role in controlling the diabetes. Tele-education is impressive due to the elimination of­­ both space and time limitation and establishing an effective relationship with client care. This study was carried out to determine the impact of tele-education by telephone and short message service on laboratory parameters in patient with type 2 diabetes. Methods: This experimental study carried out on patients with type 2 diabetes members of Urmia Diabetes Association . A total of 66 samples selected and allocated randomly in two intervention and control groups. Data gathered with demographic questionnaire and lab work. For intervention group education and telephone follow up had given for 12 weeks. Data were analyzed using descriptive and inferential statistical testes. Results: Finding of the study showed decrease in fasting blood sugar (-29.82), glycosylated hemoglobin (-0.54), cholesterol (-13.88), triglyceride (33.88) and insulin level (-4.59) in intervention group after performance of education and telephone follow up. Conclusion: Telephone follow up and tele-education have a beneficial effect on controlling the laboratory parameters in patients with type 2 diabetes .