In order to provide the possibility of defense against maneuvering targets and providing better opportunity for decisions, a general structure for different maneuvers of targets have been provided in this paper. Moreover, variety of trajectories is simulated from radar perspective and the maneuver determination is considered carefully. In order to detect and track the targets trajectory to perform a proper defense, the targets motion must be simulated so that the tracking is to be done with minimal error. In order to present a general structure for maneuvers of targets, in this paper, different models for targets trajectory in one, two and three-dimensional forms for maneuvering and non-maneuvering targets are studied and simulated. As an innovation, effects of detection and false alarm probabilities were applied to the simulations. For all the presented models, trajectory simulation was done and the results are summarized in diagrams in this paper. The results can be used for evaluating different tracking algorithms in different SNRs.

In recent years, the development of the use of location-based tools has made it possible to produce geometric trajectories from the user's movement paths. In this way, users' goal of traveling and related activities can be considered in addition to the geometry and route shape. the user activity trajectory represents the sequence of the visited activities and its related analysis as presented in many studies. In the meantime, the most important analysis is the identification of frequent patterns to predict future activities. In previous studies, only one user’ s data was used, as well as previous activities of the user were not taken into account in presented frequent patterns. For this purpose, this paper presents a framework such as After encoding the activities and forming a sequence matrix, the frequent patterns using all users' trajectories are identified considering previous activities. The proposed method also offers the ability to identify frequent patterns for the origin, destination, or interesting activity. The results of comparing the proposed method with two methods based on tree structure represent a mean of 60% reduction in computing time to form the database.

A satellite, in its orbit, is affected by perturbing forces, such as atmospheric drag, solar radiation pressure, Earth oblateness, and gravity of the celestial masses (other than the Earth). In this paper, the effects of these forces on the trajectories of different types of LEO satellites and a sample satellite (Z-SAT) are discussed. A few analyses are done on these orbits and the relevant results are categorized as substantial logics of perturbation influences on Keplerian parameters of the orbits. The "Variation of Parameters" Method is used for analyses.      

Over the last years, several differentially private mechanisms have been proposed to answer statistical queries over trajectory databases. However, most of these mechanisms aim to answer statistical queries without releasing trajectories. In this paper, we present DP-STDR; a new differentially private mechanism that releases synthetic trajectories for data analysis purposes while preserving spatial and temporal utilities. DP-STDR keeps some main spatial, temporal, and statistical properties of original trajectories and defines a new differentially private tree structure to keep the most probable paths with different lengths and different starting points. This tree structure is used to generate synthetic trajectories. Our experiments show that DP-STDR enhances the utility of query answers and better preserves the main spatial, temporal, and statistical properties of original trajectories in comparison to prior related work.

This study implemented the hand gesture digit recognition function by using the Kinect motion sensor. This interactive motion-sensing technology was employed to track, record, and convert the trajectories of handwritten numerals in space into corresponding shapes of digits on the plane. Subsequently, the feature matching method was used to achieve digit recognition. In the recognition process, first binarization and Hilditch thinning algorithm were performed on the region for recognition, and the segmentation algorithm proposed by G.E.M.D.C. Bandara etc. was used to perform segmentation of the region after thinning. This paper proposes the improvement of the conditions of the arc type of the discriminant to achieve feature extraction and enhance the digit recognition rate.