The objective of the research was to investigate the efficiency of selected methods of data fusion from visual sensors used on-board satellites for attitude measurements. Data from a sun sensor, an earth sensor, and a star tracker were fused, and selected methods were applied to calculate satellite attitude. First, a direct numerical solution, a numerical and analytical solution of the Wahba problem, and the TRIAD method for attitude calculation were compared used for integrating data produced by a sun sensor and an earth sensor. Next, attitude data from the star tracker and earth/sun sensors were integrated using two methods: weighted average and Kalman filter. All algorithms were coded in the MATLAB environment and tested using simulation models of visual sensors. The results of simulations may be used as an indication for the best data fusion in real satellite systems. The algorithms developed may be extended to incorporate other attitude sensors like inertial and/or GNSS to form a complete satellite attitude system.

Single-frame methods of determining the attitude of a nanosatellite are compared in this study. The methods selected for comparison are: Single Value Decomposition (SVD), q method, Quaternion ESTimator (QUEST), Fast Optimal Attitude Matrix (FOAM) − all solving optimally the Wahba’s problem, and the algebraic method using only two vector measurements. For proper comparison, two sensors are chosen for the vector observations on-board: magnetometer and Sun sensors. Covariance results obtained as a result of using those methods have a critical importance for a non-traditional attitude estimation approach; therefore, the variance calculations are also presented. The examined methods are compared with respect to their root mean square (RMS) error and variance results. Also, some recommendations are given.

The changes in the paralinguistic (social, economic, cultural) and linguistic sphere influence the quantitative and qualitative changes in a categorically diversified onomastic resource and the communicative flow of its elements on three levels of linguistic contact — nationwide, local and individual. The flow is additionally determined in the sphere of spontaneous everyday communication and in higher communicative functions (official linguistic behaviour). The accumulation of determinants which allow the usage of appropriate names and appellative forms (official and unofficial, e.g. diminutives, feminisms) involves the application of cumulative research methods, including psycho-, socio- and pragmalinguistic description of proper names functioning in communication. The contemporary theory of discourse in its three dimensions — formal, functional and interactional gives this possibility. It also requires the constant specification and standardization of Neoslavonic onomastic terminology.