This paper deals with the construction of nonlinear observers for navigation purposes. We first present a globally exponentially stable observer for attitude and gyro bias, based on gyro measurements and two or more pairs of vector measurements. We avoid the well-known topological obstructions to global stability by not confining the attitude estimate to SO(3), but rather estimating a full rota...

In normal working conditions it is possible to achieve sufficient attitude estimation accuracy for a satellite using regular Kalman filter algorithm. On the other hand, when there is a fault in the measurements, the Kalman filter fails in providing the required accuracy and may even collapse over time. In this paper, a Robust Kalman filtering method is proposed for the attitude estimation probl...

This study is examining the relationship between the rate of religiousity and attitude toward democracy in Nayshabor citizens. To do so, a survey was done in a sample of 295 literate citizens were selected in PPS method. Theoretical framework is selected according to the theories of Lenski, Weber and Cultural wars theory and religiosity measurement is done according to Glock and Stark’s multidi...

Little research has examined the properties of people's attitudes that predict how they will respond to conflict with others whose opinions differ. We propose that one aspect of attitude certainty-attitude correctness, or the perception that one's attitude is the "right" attitude to have-will predict more competitive conflict styles. This hypothesis was tested across five data sets comprising f...

Attitude certainty has been the subject of considerable attention in the attitudes and persuasion literature. The present research identifies 2 aspects of attitude certainty and provides evidence for the distinctness of the constructs. Specifically, it is proposed that attitude certainty can be conceptualized, and empirically separated, in terms of attitude clarity (the subjective sense that on...

Theory i s constrained by the quality and versatility of measurement tools. As such, the development of techniques for measurement is critical to the successful development of theory. This paper presents a technique -the GoINo-go Association Task (GNAT) that joins a family of existing techniques for measuring implicit social cognition generally, with a focus on attitude (evaluation). To expand ...

In this paper, the problem of attitude control of a 1D non-linear exible spacecraft is investigated. Three controllers are presented. The rst is a non-linear dynamic inversion, the second is a linear -synthesis and the third is a composition of dynamic inversion and a -synthesis controller. It is assumed only one reaction wheel is used. Actuator saturation is considered in the design of control...

Precise control of UAV (Unmanned Aerial Vehicle) or MAV (Micro Aerial Vehicle), requires the accurate determination of vehicle orientation. Attitude and heading reference systems (AHRS) are popularly used for vehicle orientation determination. In these systems, Euler angle estimation is more appropriate than quaternion estimation because the accelerometer measurement and magnetometer measuremen...

Observed and unobserved characteristics of an individual are often used by researchers to explain choices over the provision of environmental goods. One means for identifying what is typically an unobserved characteristic, such as an attitude, is through some data reduction technique, such as factor analysis. However, the resultant variable represents the true attitude with measurement error, a...