Swedish Defence Research Agency

About: Swedish Defence Research Agency is a government organization based out in Stockholm, Sweden. It is known for research contribution in the topics: Radar & Synthetic aperture radar. The organization has 1413 authors who have published 2731 publications receiving 56083 citations. The organization is also known as: Totalförsvarets forskningsinstitut.

A Method for Community Detection in Uncertain Networks

Abstract: Social network analysis can be an important help for military and criminal intelligence analysis. In real world applications, there is seldom complete knowledge about the network of interest -- we only have partial and incomplete information about the nodes and networks present. Community detection in networks is an important area of current research in social network analysis with many applications. Finding community structures is however a challenging task and despite significant effort no satisfactory method has been found. Here we study the problem of community detection in noisy and uncertain networks with missing and false edges and propose methods for detecting community structures in them. The method is based on sampling from an ensemble of certain networks that are consistent with the available information about the uncertain networks.

A mouse model for in vivo tracking of the major dust mite allergen Der p 2 after inhalation.

Abstract: A mouse model for in vivo tracking of the major dust mite allergen Der p 2 after inhalation.

Scenario-based evaluations of high-accuracy personal positioning systems

Abstract: Foot-mounted inertial sensors combined with GPS-receivers, magnetometers, and barometric pressure sensors have shown great potential in providing high-accuracy positioning systems for first responder and military applications. Several factors, including the type of movement, surface, and the shape of the trajectory, can strongly influence the performance of foot-mounted inertial navigation systems. There is a need for realistic scenario-based evaluations as a complement to the controlled environment tests that have been published in the literature. In this work we evaluate the performance of a foot-mounted inertial navigation system using three-axis accelerometers, gyroscopes and magnetometers during realistic scenario-based measurements. The position accuracy is evaluated by using a camera-based reference system which positions itself towards visual markers placed at pre-surveyed positions, using a slightly modified version of the ARToolKitPlus software. Maximum position errors of 2.5 to 5.5 meters were obtained during four separate high-tempo building clearing operations that lasted approximately three and a half minutes each. Further improvements in accuracy, as well as improved robustness towards different movement patterns, can be achieved by implementing an adaptive stand-still detection algorithm.

Sea floor classification with satellite data and airborne lidar bathymetry

Abstract: While land maps of vegetation cover and substrate types exist, similar underwater maps are rare or almost non-existing. We developed the use of airborne bathymetric lidar mapping and high resolution satellite data to a combined method for shallow sea floor classification. A classification accuracy of about 80% is possible for six classes of substrate and vegetation, when validated against field data taken from underwater video recordings. The method utilizes lidar data directly (topography, slopes) and as means for correction of image data for water depth and turbidity. In this paper we present results using WorldView-2 imagery and data from the HawkEye II lidar system in a Swedish archipelago area.